With Drago receiving the Element from the now departed Neo, the Brawlers decide to head back to Neathia to help fight off the Gundalians. Before they can do so, Dan must say goodbye to Julie, who hastily borrows his bike to get to her cheerleading practice. Meanwhile, Ren sends Zenet to steal the Element back via trickery. So, she disguises herself as Julie and tries to take Drago. However, her plan is foiled when the real Julie shows up, throwing Dan and Drago into confusion! However, when he reveals he is leaving for Neathia to help fight, the real Julie expresses that she is ok with it and hopes they succeed, assuring Dan that she is the real Julie. Zenet is forced to reveal herself and battles Drago. She tries to trick Drago by transforming Contestir's appearance, but Drago overpowers her with his new Battle Gear Cross Buster. Zenet retreats and informs Ren that the Brawlers are heading to Neathia. Ren runs to them before they go, but arrives just as they leave with Julie cheering them on, commenting that they will meet soon again.

Dan must battle the Pyrus Lord, Apollonier, in order for him and his friends to return to their world. He and Drago soon find out that they're battling a clown. Dan manages to win the battle, but Drago doesn't evolve. When Dan rips off the clown's mask, it turns out to be Runo. In order for Drago to evolve and Dan to past his test, he must battle, and win, against each of the Brawlers.

Marucho must battle the Aquos Elemental Warrior, Frosch, and he is forced to send in Preyus early when he learns he is battling a shadow of himself. Preyus isn't feeling well throughout the battle, but he is able to give Marucho guidance to accepting his past. Marucho knew that he only did what his parents told him to make them happy, but he didn't like to always be so obidient. This causes Marucho to hate his old self. By accepting the past him, Marucho was able to help Preyus' digestion problem. This allows Preyus to evolve by spitting out his brothers: Aquos Angelo/Aquos Diablo Preyus. Will the combined strength of these brothers prove to be enough to defeat the Aquos Warrior?

The Brawlers head to face Masquerade in one final battle.

Dan is upset about losing Drago but tries to move on and think of ways to get him back: starting with all out intensive training. Meanwhile on New Vestroia, Mylene wants to close to portal to keep Dan and the others on Earth, but Prince Hydron orders her not to, so as to allow Spectra and Gus time to return, which angers Mylene, who greatly enjoys her new power. Apollonir states that they must retrieve Drago as the Perfect Core is losing power and the other two dimension controllers are growing stronger. While training, Dan faints and develops a fever. He runs out into the park calling out to Drago, lamenting over how he lost Drago. All of a sudden, Apollonir shows up and to retrieve Drago, but Dan regrets to inform him that he lost Drago. Apollonir is disappointed that Dan has given up so easily and suggests that Drago is also upset at himself for losing the battle and letting Dan down. Dan wakes up, with his fever broken, to find that Apollonir has crossed over to Earth. Apollonir, linked to the Perfect Core like Drago, and is easily able to find Spectra and teleport everyone there. Spectra accepts Dan's challenge but brings out Helios to test if Apollonir is worthy of fighting Drago. Apollonir lectures Spectra on true Bakugan spirit but Spectra believes that power is the only way to win and brings out his Bakugan Trap Metalfencer. However, Apollonir easily takes them both down in one hit. Spectra finally sends out Drago, but Dan is shocked to see his friend has been altered in appearance while under Spectra's control.

In the Doom Dimension, the Legendary Ancient Warriors of Vestroia prepare to test the powers of the Brawlers, seeing if they are worthy enough to save Vestroia. The Brawlers are separated and Julie is left with Gorem to face the Subterra Warrior, Clayf, and a shadow of her perfect sister, Daisy. With help from Gorem, Julie learns that she isn't her sister and she can only do the best she can do. Because of this, Gorem evolves into Subterra Hammer Gorem, and defeats Clayf.

Alice appears to be disappearing all the time. Dan goes to talk with Marucho, Runo, Shun, and Julie and ends up finding Alice! Alice won't explain anything and leaves. Later, Joe receives a message from Masquerade, and Dan decides he'll take over to fight Masquerade with Drago to end it once and for all with Masquerade. Dan wins and offers Masquerade to join the Battle Brawlers to help defeat Naga. But Masquerade refuses and takes off his mask. It is revealed that Alice was Masquerade the whole time!

The Brawlers are having trouble finding the Infinity Core. When they learn that their location might be being broadcasted, they shut off their signal.

Runo and Tigrerra must battle a young boy from Runo's past (a smaller version of Dan) summoned by The Haos lord, Lars Lion. The test is for Runo to realize how much she truly treasures her and Dan's friendship/love. When Tigrerra is getting hit by Lars Lion's piercing arrows of light, Runo realises the friendship/love that she treasures and says "We are Friends Forever Dan!" in the English dub, while she says "I love you Dan!" in the Japanese Version. When Runo realizes this, Tigrerra evolves into Haos Blade Tigrerra.

Shun is stuck with the female Ventus Lord, Oberus, who has summoned a child that looks like Shun's mom to battle. The child convinces Shun to play with her while the sun is still setting, which it never does. Shun must battle himself as well when he is forced to choose between going back or staying in this world with his mother. In the battle with Oberus, Shun believes that he doesn't need his friends. His belief causes Skyress to die after a great impact with Oberus. When Shun realises his mistake, a tear drops down onto Skyress' ability card, changing it, and miraclesly reviving Skyress, which evolved into Storm Skyress. In the end, when Shun chooses to return to his world, Skyress evolves to Ventus Storm Skyress.

Marucho reveals that he secretly moved to Dan's neighborhood, and throws an elaborate welcome party. Masquerade makes a business offer with the famous pop band duo, Jenny and Jewels. The duo crash the welcome party, and challenge the Battle Brawlers.

While at an amusement park, Dan and Runo are invited onstage to assist a magician act by two brothers. Dan picks a card, and realizes it's a Doom Card. The brothers are working for Masquerade, and Dan and Runo get tricked into a battle.

Marucho and Runo realize that the combined powers of the Bakugan Brawlers are not enough to defeat Masquerade. Without Dan's knowledge, they visit Shun to try and get him to join. Shun's grandfather tries to get them to leave, but Shun makes a deal. If they win, he joins. If they lose, he'll walk away.

Dan and Marucho fight against the pop star duo, Jenny & Jewels. After a narrow victory, Drago tells the Brawlers about how the Bakugan came to Earth, and how a human entered the Bakugan world of Vestroia.

After the battle with Lync and Volt, Dan, Drago, and Marucho go with Mira to the Resistance base. Along the way, Mira reveals that only a few people of the Vestals realize that the Bakugan are intelligent creatures, while the rest of the people have not been told. She reveals that after discovering this for herself, and becoming outraged with her father for participating in the capturing of the Bakugan, she ran off and created the Bakugan Brawlers Resistance, joining with people who thought as she did. Upon arriving at the base, they meet Baron, a major fan of the Bakugan Battle Brawlers and the 6 hero bakugan. Shortly after, another Resistance Brawler named Ace, highly disapproves of Mira bringing humans to aid in their quest to free the Bakugan. Instead, he challenges Dan to a battle, and says that if he beats him, he and Marucho can join the Resistance in their quest to save the Bakugan. Dan gets off to a rocky start, but he and Ace are too evenly matched. With one win and one loss for each their battle ends in a tie and they become fast friends.

Alice arrives in Vestroia as Masquerade in order to help her friends. Masquerade finds Dan and he begins to help the weakened Dan and Drago. Centorrior and Druman though are able to counter sound judgment and all the power-ups that their Bakugan are given. Dan and Masquerade must work togerther to defeat Centorrior and Druman alongside an army of Serpenoids and Gargonoids. With Masquerade and Hydranoid using a cut and run trick, Dan and Drago lure them to the right spot where Hydranoid's attack manages to defeat Centorrior. Drago then uses his attack to defeat Druman. Masquerade then fades away encouraging Alice to continue on being a Bakugan Brawler and Alice obtains Hydranoid in the process. When the Brawlers reunite with each other, Centorrior and Druman watch from afar and stated that they are together just as Naga planned it to be.

Hal-G appears to explain the origin of Alice and Masquerade. Because she is unable to forgive herself, Alice then disappears. Meanwhile a huge hole opens up in the ocean and weird weather has been happening all throughout the earth. Through much convincing, the Brawlers convince their parents about the Bakugan. What will they find in the decaying Vestroia? Dan and the Brawlers decide to take a little road trip, to Vestroia!

Klaus, Chan-Lee, and Julio return to finish off the Brawlers. Dan, Runo, and Marucho take them on, but what will happen when Klaus uses Marucho's stolen Bakugan?

When Shun leaves the group, Alice chases after him. Meanwhile Dan goes to take on Masquerade alone.

The Brawlers finally meet Julie up close and personal, but the mood goes from happy to sad when they see what's happening in Vestroia. Julie and Shun fight with Julie's friend Billy, the 9th ranked Bakugan player, and her neighbor Komba, the 5th ranked Bakugan player, knowing they were tricked by Masquerade to take out Dan and the rest of the Brawlers.

Lured by an invitation to celebrate their world class rankings, five of the top ten Bakugan players gather at a mysterious mansion. There they meet Masquerade & the evil Bakugan "Naga". They're put under a spell to take Dan & the other Battle Brawlers out of the picture. Meanwhile, Alice confesses that she believes that her grandfather Michael is responsible for the destruction of Vestroia. They decide to take a look around Michael's lab to find evidence of what happened to him.

Naga's troops have finally infiltrated Wardington after two defeats. Alice discovers that Tricloid's sister Rabeeder is invading the town. Little does she know the one she trained, Christopher, will also get involved in the battle. Dan is informed that Hairadee, Centorrior, and Druman are also approaching the city following Tayghen and Tricloid's defeat. When it appears these two are being overpowered, Klaus arrives. The three soon realize all that Rabeeder is doing is being controlled by her worry for her sister Tricloid. Alice starts doubting herself but Christopher helps her. Hydranoid defeats Rabeeder and is reunited with Tricloid as both of them return to Vestroia.

The Battle Brawlers have managed to unite each element together, and they are given the blessing as the six new warriors. Hal-G and Naga are still causing chaos over Vestroia though, and now they are attacking Earth with the help of the hybrid Bakugan (Taygen, Hairadee, Rabeeder, Tricloid, Centorrior, and Druman) leading their Bakugan armies. The Brawlers must figure out how to save both worlds. Help is on the way though. Chan Lee, Billy Gilbert, Komba O'Charlie, Julio Santana, and Klaus Von Hertzon lead every Bakugan players of the world when they have decided to give assistance. Once Naga starts attacking with negative energy, his minions get charged up to turn the tables against the Bakugan players. Joe contacts the Brawlers that Naga in the real world. Drago senses Wayvern is in trouble when he sends his minions to find the Infinity Core, so the Brawlers head back to take on Naga.

Joe shows up after Dan defeats Julie, Marucho, and Runo for Wyvern to check out Drago's battling skills when Dan and Shun have their battle to finish Dan's test. Meanwhile, the Darkus Lord and Masquerade finish their battle. In the end Drago beats Skyress and becomes the Pyrus Ultimate Dragonoid, and Duel Hydranoid beats the Darkus Lord and evolves into the Darkus Alpha Hydranoid.

The Brawlers have been pushed back, but will the return of Preyas and the evolution of Drago be enough to bring them to victory?

Dan has a hard time adjusting to life without Drago. He ends up causing a schoolmate named Ryo to drop his computer and runs away, hurting Ryo's feelings. Masquerade takes advantage of Ryo's hurt feelings, and Ryo beats Dan in a battle. Dan finds Drago, and tries to make up with Ryo.

Masquerade teams up with a player with Rikimaru, by giving him a very special Bakugan. When Rikimaru and Dan battle, Drago ends up using a dangerous move to save himself and win the battle. Dan gets angry, and throws Drago into a river, cursing the day they met.

After a quarrel between the Brawlers, they all go separate ways. Julie decides to pursue her friend Billy and try to save him from Masquerade's evil ways.

Alice realizes that she may have a connection with the mysterious Hal-G, but doesn't have the courage to tell the other Brawlers. Meanwhile, Dan recalls the last battle he had with Shun. Shun's mother gives Shun a Bakugan, "Skyress", to watch over him.

Masquerade has been destroying the Bakugans of kids all over the world, and the Brawlers have to put a stop to it. Reluctantly, Dan accompanies Runo and Marucho to Shun's house to recruit him one more, but find out he's joining Masquerade! Dan accepts the challenge of battle, and with Drago, fights against Shun and Masquerade.

Masquerade manipulates two boys, Kosuke and Takashi, into using his Doom Cards against the Bakugan Battle Brawlers. He promises that he'll reunite their friend Ai with her brother if they help him. Wanting to help their friend, they take the bait and soon run into Runo and Marucho, who are at the airport to pick up their website friend, Alice. Luckilly, Alice is skilled in the finer points of combination battle, and coaches her friends to victory. Alice has a secret, however, that might just ruin her friendship with the Brawlers.

Dan's final test is to beat his friends so his Dragonoid can evolve to the next level and become the Ultimate Bakugan. Dan battles Runo and Shun while Masquerade goes to see the Darkus Lord, Exeedra, and he ends up fighting Alice as a mirage.

Joe is determined to find out where his friends have gone, so he challenges Masquerade to a battle. At first Joe appears to be outmatched, but Wyvern returns to give Joe assistance. The Brawlers also return, and Masquerade realizes his battle is only beginning. Dan explains everything about the Bakugan to his mother, who believes him and asks Drago to take care of him. Naga is revealed as one of the most dangerous Bakugan in the world.

When Marucho loses his Bakugan to Klaus, he and Runo give chase, and wind up in Masquerade's castle!

Hydron discovers that a fellow prisoner is none other than Gus Grav, who was presumed dead in episode 39. Meanwhile, Runo, Julie and Mira prepare a cake for Keith to officially celebrate his joining the Resistance. However, Keith's mind lingers elsewhere, something that Mira notices but Keith brushes off. Dan suggests that instead of waiting for Zenoheld's attack, they storm the palace. Keith, however, is too impatient and takes his ship to the Vest Palace on his own. A battle quickly ensues and Gus feels Spectra needs his help, so he tricks Hydron into battling so their bakugan can free them from their cells and Gus leaves to help Spectra while Hydron is left on his own. When Zenoheld nearly defeats Spectra, Gus arrives in the nick of time, shocking Spectra who is happy finding out that Gus had survived. The two then battle together, giving them the upper hand against Zenoheld. Partway through the battle, Prof. Clay informs Zenoheld that the Alternative System, a giant airship modeled after Farbros, is complete and targets Spectra and Helios for a test fire. The blast sends Spectra's ship flying and takes a huge chunk out of a small planetoid, with Spectra and Gus just barely escaping the impact. Farbros links with the Alternative System and King Zenoheld declares his quest for intergalactic domination to begin.

As the remaining Brawlers enter the hybrid world of Subterra and Haos, a pair of Subterra/Haos Bakugan sisters named Rabeeder and Tricloid fall in love with Dan. The sisters say the only way out is if they beat them in a race. Dan and Drago win and leave to the next world.

Spectra makes a false appeal to the Vestals that he is the hero and is trying to stop Zenoheld from ruling all dimensions. On Vestal, Dan and the others purpose to stop whatever he is planning. Zenoheld and the Vexos realize that Spectra has stopped their ability to travel into Vestal by jamming their signals, so Zenoheld sends Shadow to earth to force Dan and the resistance to come to them. Shadow appears and frightens Alice until Chan Lee arrives and the three battle. Alice is initially hesitant to fight, as she might become Masquerade again, but eventually embraces the fearlessness of Masquerade and utterly destroys Shadow's Hades. However, Shadow then reveals his more powerful spider-like Bakugan and wins the battle in one turn. As a result of Darkus Fortress' attack, Dr. Michael's transporter system is destroyed leaving Dan and his friends trapped on Vestal. Meanwhile, Prince Hydron plans to travel to earth to lure Dan and his friends there.

With Keith having gone to the palace and having no way to find said palace, the Resistance are stuck. Luckily Alice and Dr. Michael arrive and use the teleportation signature left behind by Shadow and Mylene to back track to the palace. Meanwhile, Zenoheld continues his attack, forcing Spectra and Gus to retreat and come up with a plan of counter attack. The Resistance are saddened to hear that Tigrerra and Gorem do not wish to participate on the assault of the palace due to the fact that they know their limitations (which are lower than the rest of the team) and it would irresponsibly put Runo and Julie in danger. All of a sudden, Dr. Michael locks onto the palace's coordinates and the Resistance - minus Runo, Julie and Alice - head for the battle and arrive just in time to see Helios and Vulcan in trouble. However, the Alternative is far more powerful than any of them could have ever imagined (because despite the amount of damage they did, which was a pretty decent amount, the Alternative still repaired itself with Farbros). Keith realizes that because Prof. Clay built the Alternative, that he must be inside and asks Mira if she wants to confront him, which she does. Then, Keith uses a new battle gear, the Zukanator, on Helios, in hopes that it will even out the playing field. Keith blows a hole in the Alternative and he and Mira enter the machine.

The Bakugan Battle Brawlers enter Vestroia and realize Vestroia has become a hybrid world where two elements are mixed together to make one element together. They enter the Ventus and Aquos world where they meet Tayghen and Hairadee: two Bakugan of both Ventus and Aquos elements. As they fight, they suddenly see the portal to the next hybrid world of Vestroia is closing and so they agree that Shun and Marucho are to stay in the Ventus and Aquos world to defeat the two Bakugan. The rest of the Bakugan team disappear through the portal into another dimension of Vestroia.

With the Vexos losing one by one, Gus Grav calls them all together to explain that the Resistance has to be defeated. So Gus decides to take matters in his own hands and confront the Resistance, and bring pride back to the Vexos. Meanwhile, the Resistance makes a stop en route to Alpha City, where Mira gives Dan a Bakugan Trap called Scorpion to help in his battles. Not much is known about the Trap Bakugan except that they are incapable or unwilling to communicate. Excited, Dan takes off to get in some training with Scorpion. Just then, Gus shows up and starts to mess with Dan's head, asking what he will gain from saving the Bakugan, leaving Dan with this question. He returns later, asking Dan what the answer is to his earlier question, and it is revealed that he is the number two brawler among the Vexos. Feeling confident, Dan decides to take him on, but is soon overwhelmed with the power of Gus' Bakugan Subterra Primo Vulcan.

With Ace and Marucho captured by the Vexos, Shun decides to head to Beta City alone to destroy the controller. On the way he is ambushed by Shadow Probe who is armed with Darkus Hydranoid! In the middle of the battle, Shun and Ingram realize that it is not the same Hydranoid they know, it is really mechanical bakugan Darkus Hades in disguise. Darkus Hades was created from Hydranoid's DNA and has none of the weaknesses that Altair had. Shun tries his best to hold his ground by Ingram and Hylash are no match for Hades and Bakugan Trap Darkus Fortress. Shun contemplates throwing in the towel out of fear for losing his partner like how he almost lost Skyress in a tough battle, but Ingram convinces him otherwise and that he will always be there. Shun is defeated by Shadow and passes out. The Vexos, having now captured the rest of the Resistance, plan to keep them as hostages while keeping Dan and the others stuck on Earth forever and while they take all Bakugan.

The Brawlers return back to Earth and see Shun, Runo and Julie waiting for them. In order to evade the Vexos, everyone stays at Marucho's house which is equipped with a shield to hide the attribute energies' signal. Runo gets into a fight with Dan and thinks that he thinks that she's not strong enough to face the Vexos. Runo wanders out into the city hoping to draw in the Vexos, but Mira follows her and they are ambushed by Lync and Mylene. Things go bad and Mira loses her Subterra energy, making the Vexos one step closer to activating the Bakugan Termination System.

Baron's little sister, Maron, uses Klaus' transporter to visit Baron, so Julie and Runo suggest to him to show her around town. Meanwhile, Shun sneaks away from Marucho's house an travels to the Samurai theme attraction in the same park that Baron and Maron are at. Shun encounters Volt disguised as a samurai and a battle ensues. At the same time, Baron activates his gauntlet to show Maron how it works and learns of Shun and Volt's battle. The two easily overpower Volt, keeping the Ventus energy safe. Maron bids farewell and thanks everyone for the great day and departs, not before thanking Shun for saving her and kissing him on the cheek.

The peace of New Vestroia does not last long. A race called the Vestals invade and colonize New Vestroia, turning the Bakugan back into balls and making them their slaves for amusement, not knowing that Bakugan are intelligent creatures. One by one the six fighting Bakugan are captured leaving only Drago. In an effort to stop this, Drago is separated from the core of Vestroia by the six legendary warriors, and heads to Earth to seek out Dan Kuso, and the two leave for New Vestroia, with Marucho following after overhearing Drago's plan to leave the others behind. After they learn that the Vestals are responsible for the state New Vestroia has fallen into, he challenges Lync Volan and Volt Luster, two members of the Vexos. A Vestal named Mira, part of the Bakugan Brawlers Resistance, interrupts and tells Dan of the new brawling style required for Bakugan battles. Dan manages to adapt to the new method quickly and wins two Bakugan from Lync and Volt.

Tensions form between the group of Brawlers when it is believed that one of them is a double agent.

Seeing how desperately he needs a partner to help Dan and the Resistance, Marucho takes his gear and heads out, in search of a Bakugan to battle with. At the same time, Mylene also goes hunting for Bakugan, after throwing away three she claimed useless. In the morning, Marucho meets Aquos Elfin, a Bakugan who turned out to know and have what might be a crush on Preyas. She explains that after his capture, she had to watch over the forest and protect the Bakugan living there from any harm. When Marucho asks to be partners with her, she at first declines because she claims to be "waiting for the right partner". But when Marucho explains that he needs her to help free the Bakugan (as this was what Preyas would have wanted) she says that if he passes her test, she will at least think about a "temporary partnership". As the testing goes underway, with Marucho not doing so well, Mylene flies over, and in fury, Elfin and Marucho demand she and the Vexos return the stolen Bakugan. Angered at how cruel Mylene is to the Bakugan she already carries (by throwing them away like trash), Marucho and Elfin challenge her to a brawl. But Mylene soon begins to show her skill, and may end up winning Elfin as a new Bakugan! just when all of mylene's bakugan were no use, she unleshed a bakugan called a bakugan trap. Just when Mylene is about to seize Elfin, a hooded figure wielding Ventus Bakugan arrives and saves Marucho. Mylene states she's tired of losing to this hooded person and offers him to join the Vexos, but he leaves without saying a word and Mylene departs. Meanwhile, Marucho slowly awakens, despaired that Elfin was gone. But as it turned out, Elfin was merely off to find him some water, and then begins explaining how she couldn't let anything happen to her "goofy partner". In the end, Elfin and Marucho are partners, able to aid the Resistance in their journey. Later, in episode 6, it is revealed that the hooded figure is Shun.

Mira, Dan and Marucho head to Vestal to meet Klaus, Baron and Ace at Klaus' mansion. It is there Volt comes to retrieve the Pyrus energy after being humiliated by Prince Hydron. Volt and Dan are about to battle when Spectra and Gus appear out of nowhere. Gus attacks Volt psychologically by saying he stole Brontes' soul, as shown in the beginning of the episode. Volt backs away to let Spectra brawl Dan. Mira, Magma Wilda, Marucho and Elfin Version II join in the brawl to help Dan and Drago. In the brawl Dan manages to defeat Spectra after a three minute long battleand using the power Drago received from Apollonir, despite Helios's upgrades. However, before Spectra leaves, he warns Dan that they will meet again.

It's an all new adventure for the Bakugan Battle Brawlers when Dan's family moves to Bayview City and Marucho's Bakugan Interspace becomes fully operational to everyone, allowing kids all over the world to log on and display their battling skills. Dan heads to a cafe in town where Julie works to meet with his new friend Jake, a young brawler who is new to the game. The two make there way to Bakugan Interspace where they meet up with Marucho who gives Jake Subterra Coredem. Dan and Jake immediately want to battle, but discover that all the available arenas are occupied. They eventually meet up with Ren and Shun, who is locked in battle with Shuji. With Shun quickly seizing victory, Ren is scheduled to battle Dan next. As the battle intensifies, Marucho is forced to shut down Bakugan Interspace and Dan is knocked out cold. Before coming to, Dan has a vision of Bakugan at war each other, something which everyone, except Ren, brushes off as a hallucination.

The Brawlers mourn over the loss of Dan and Drago. Meanwhile, Shun gets a challenge from Masquerade and decides to join Dan in the Doom Dimension. When Skyress learns of this plan, she tries to gather the other Bakugan and try to save Vestroia without putting their human partners in risk. Soon, the other Brawlers catch onto his plan and decide to join him, but first Runo makes a promise to Dan's mom - he's safe and will be home soon.

Wayvern puts up an energy shield around Wardington powered by the Infinity Core to hold off Naga and his troops. Meanwhile the Brawlers return and join in the battle to protect all of Earth and defeat Naga before he can join the two cores together. Failure means that both worlds will be destroyed. Jenny, Jewels, and Marucho protect the city via sea, where the Ventus/Aquos hybrid Tayghen has been creating tsunamis. The singing of Jenny and Jewels gets Bordington's fans to come out and cheer. Can Marucho, Jenny, and Jewels defeat Tayghen?

The battle against Naga's troops continues as Julie and Billy team-up to take on the Subterra/Haos hybrid Bakugan called Tricloid, who has been powered up by Naga negative energy. At first the two seem to be overpowered, but the adaption of each other's battle styles may be what's needed to help them realize how to work as a team again, especially when Naga decides to crash the party. Shuji and Akira also appear trying to get strategies from their sister Nene. With help from Nene and her Ravenoid, Gorem and Cycloid defeat Tricloid by getting rid of the Negative Energy that Naga placed on her. At the end, Julie asks Billy out on a date.

The return of Naga's Ventus/Aquos servant hybrid Hairadee has brought new troubles for Komba and Shun. While Skyress is trapped in a barrier of ice, Shun reveals his ninja skills to free Skyress and defeat the hybrid. Julio crashes the party and helps the battle. Will the three of them be enough to take Naga's servant on?

Wayvern is calling to Drago to tell him that she needs help, the top ranked Brawlers must defeat Centorrior and Druman. Meanwhile Naga's negative energy is proving to be too much for Wayvern and Fortress. With Centorrior defeated, the others deal with Druman as Dan and Drago head over to where Naga. When Drago arrives, he fights Naga. With help from Julios, Runo has Tigrerra destroy Druman. Wayvern asks Drago to attack her so she can give him the Infinity Core. He does so, and Wyvern disappears. Drago becomes Infinity Drago. Drago then continues his fight with Naga. They both have 1000 Gs. In an epic battle, the two seem evenly matched. However, Hal-G sends out his 5th Paladins to assist Naga.

As Hal-G releases 5th Paladins, all seems hopeless until the Brawlers send their Bakugan to aid a wounded Drago. They destroy the 5th Paladins as Naga absorbs the 5th Paladins' energies. With the last of his power, Drago fires a brilliant burst of fire.

When Prince Hydron is furious because of his incomplete collection, Spectra and Gus challenge Dan to a battle in an effort to catch Drago. While the Resistance plans to attack Alpha City, Mira wants to take a short detour to find her brother. It is hinted in this episode that Ace starts to like Mira, during in the arugment, he seems and sounds like that he was worried about her going somewhere that might be dangerous. In the midst of the argument, Dan sneaks away with Drago to fight Gus and manages to battle well until Spectra joins in and Dan starts to struggle in the fight. Out of nowhere, Shun comes to his rescue. Shun beats Gus and Dan beats Spectra when Drago displays a massive power surge due to Helios' taunts about Tigrerra. Seeing that huge amount of power Spectra shows hint of betrayal when he said that he won't let the magnificent Bakugan become a play thing, meaning that he won't give it to Prince Hydron if he captures it. Back at the base, Shun explains that while he was in the mountains a portal opened up right in front of him and got sucked through to New Vestroia. After he rescues Ingram from the Vestals, she remained in his debt and the two banded together to free the Bakugan. As they make their way closer to Alpha City and the dimension controller, Dan asks why Shun didn't reveal himself earlier when he rescued Marucho. Shun explains that he had something important to attend. When they approched Alpha City, Shun revealed he'd break in the city and find his Skyress.

After Shun successfully leads the Resistance into Alpha City, Mira departs on her own mission: searching for her older brother, Keith. She heads to her home to search for clues on her brother's computer but comes up with nothing. After her father, Dr. Clay, arrives, she confronts him and he simply says that "He is no more." When she further questions him, he leaves for his lab, while Mira follows. Meanwhile, Shun takes the others to check out the control spire and they learn that the battles that take place in the arena below the controller are synchronized with the controller's power. At the lab, Mira witnesses the birth of the first cyber Bakugan: Altair. As the boys make their way to her location, Mira is confronted by Lync, who is armed with Altair. During the battle, Mira seems to have the upper hand with Wilda and her trap Baliton. That is until Lync activates two Double Abilities in a row. The scientists are worried about Altair's power fluctuation but Dr. Clay orders Lync to destroy Wilda and Baliton. Before he can, the massive overload causes Altair to crash and shut down, ending the battle. Dr. Clay decides to use the data to perfect Altair into the most powerful Bakugan ever.

Ace and Shun team up in a Bakugan battle tournament in order to overload the dimension controller because it draws power from bakugan battles. After Marucho is disquaified in the singles round, he sneaks the others in. They almost get caught by some guards until Mira pretends to be a huge Vexos fan and they manage to slip away. As they remain hidden, the Vexos show up and Mira notices that Spectra tosses his Bakugan the same way as her lost brother Keith (later realize that Spectra might have somthing to do with the disappearance of Keith). Meanwhile, Ace and Shun are having trouble getting along in the battle tournament and are starting to lose against the Dark Angels who are Vexos wannabes. When their opponents begin taunting them, Shun and Ace put their differences aside and finally come up with a plan. They win with ease while claiming their opponent's Bakugan. Shun and Ace prepare for their match against Lync and Volt.

Shun and Ace have made it to the finals and they prepare to battle Lync and Volt. they were brawling with altair and volt's new bakugan, brontes. Meanwhile, Dan and the others head to the dimension controller, but lose Marucho on the way! Things only get worse when they discover many other talking bakugan and then they are captured by guards who are marveled by the speaking Drago. Just then Marucho drops in and saves them. Things get worse for Shun and Ace when Lync combines his Ventus Altair with Ventus Wired and their bakugan traps seem to have no effect. Shun and Ace discover Altair's weakness: it cannot sense multiple opponents and they manage to destroy it. While the others hold off the guards, Dan makes his way to the controller, finding that it is guarded by lasers. He throws Drago through the lasers and he hits the reverse switch, destroying the controller just as Shun and Ace defeat Lync and Volt. The newly freed bakugan rise up from the ground and everyone in the stadium learn the truth about the bakugan.

Mira and Baron are stuck on Earth so Mira decides that they need to take a break so they go to an amusement park. Mira and Julie are separated from the rest of the group and run into Spectra and Gus who say that they came back to Earth by tracking down Dan's Gauntlet to the amusement park. Mira wants to know if Spectra is her brother Keith so she decides to brawl against him. However, Gus rearranges their little deal so she battles Gus instead. If she wins, Spectra takes off his mask but if she loses, she has to join Vexos against Prince Hydron. At first Mira struggles against Gus' abilities, but with help from the original Subterra master Julie and her copycat ability card, Mira pulls through and defeats Gus. Despite Gus' attempts to dissuade Spectra, he removes his mask and is revealed to truly be Mira's brother Keith.

Marucho finds himself in a desert with Elfin. After falling into quicksand, he is rescued by Volt who later engages him in a battle. Marucho seems to be doing well with his new trap, Tripod Epsilon but when Volt pulls out his trap, Dynamo, things get rough and Marucho is defeated. Back on Earth, Mira and Baron hang out at Dan's, who after waking up from a dream, is still eager to return to New Vestroia in order to help Shun and Marucho.

Spectra and Gus, stuck on Earth, stay in an abandoned factory. When Gus returns with "juice in boxes",(there's no such thing asjuiceboxes on Vestal) he finds that Spectra is gone. While Dan trains Baron, Spectra runs into a fortune teller who tells him that if he stays on the path he's chosen than he will meet his end, but Spectra does not listen to her. Spectra decides to take Drago by force, now being tired of waiting for Dan to join him. He sends one of Gus' hornets to challenge him and they meet in the arena where he last fought Masquerade. Mira, Baron and Runo worry about Dan being out on his own. In the first round Dan takes a major loss, but manages to strike back with Pyrus Scorpion. But then Spectra pulls out his own mechanical Bakugan Trap Pyrus Multisided Metalfencer. Helios gets frustrated and demands that Spectra gives him more power. Spectra willingly obliges and activates a forbidden ability card to give Helios absolute power. Dan and Drago are disgusted by this massive power and what it could do to Helios, but neither Spectra nor Helios seem to care about the consequences. Drago is no match for this power and loses, with Spectra claiming him as his prize. Dan is crushed by his defeat and the loss of his partner while Spectra walks by the same fortune teller who is shocked by how much darker his future has become. Once again, Spectra does not care.

As Dan and Baron safely make it back to New Vestroia, they find their base completely empty with no sign of Shun, Ace or Marucho anywhere. They discover that they are near Beta City and resolve to head there believing that Shun, Ace and Marucho have gone there. Meanwhile, as Spectra makes his return, the other Vexos are shocked to see that Mira is with him, saying that she has joined the Vexos. However, in her mind, she only wants to find out what Keith is really up to. Also, she discovers that Shun, Ace and Marucho have been captured and are being held hostage. She tries to release them. Dan and Baron sneak into Beta City and battle Mylene and Shadow. Meanwhile Mira is interrupted by Spectra who helps her release her friends, but he tells her that she owes him a debt. As the battle wages on, Baron is defeated defending Drago, who taps into the power of the Perfect Core, defeating Mylene and Shadow easily as well as destroying the dimension controller. Ace, Shun and Marucho reunite with Dan and Baron and they make their leave from Beta City. Later, Mylene accuses Spectra of her loss and the escape of the prisoners but Gus reminds her that she lost the battle, not him. Mira is still left wondering what her brother is up to.

Mira is uncertain of her brother's intentions while in Gamma City. Meanwhile, Ace is unconvinced that Mira has betrayed them due to his feelings for her, but they all resolve to head to Gamma City for the final controller. That night, Spectra invites Mira to dinner where he asks her to join him because he needs her and cannot accomplish his goal without her. Mira is unsure and retires for the night. Later she contacts Spectra asking to battle him and let that decide her fate: if she loses, she will serve him but if she wins, he must go back to being her brother. However, after Helios has volunteered to become a cyborg bakugan after Prof. Clay had collected data on Drago while he was in Spectra's possession. Wilda and Baliton prove to be no match for Cyborg Helios and Mira loses.

Mira and Spectra meet with Prince Hydron, who shows her his collection and later receives a message from his father, who is angered by the destruction of the other two controllers. Hydron then orders Mylene to divide and conquer the Resistance, since she has shown that they are weaker on their own and orders Lync to keep an eye on Spectra and make sure that his new mechanical bakugan is ready for battle. The Resistance arrives and Ace and Baron explain that the controller is underground and is the most powerful. They all head in but encounter Volt. Baron deals with Volt while the others proceed discovering that Gamma City is not a real city but a research facility. All of a sudden, Shadow and Mylene appear and Shun and Marucho step in to battle. Spectra takes Mira to see a team of special mechanical bakugan that he and Dr. Clay had designed themselves that were intended for Hydron but he intends to make certain that they only obey him. Spectra then orders Mira and Gus to use the bakugan to battle Dan and Ace to collect data on Drago and Percival. Meanwhile, the others gain the upper hand against the Vexos. Dan and Ace continue to the controller but encounter Gus and Mira. Ace is shocked that Mira has truly betrayed them and Gus orders Mira to prove that she is loyal to Spectra.

Dan and Ace engage Mira and Gus in battle against their mechanical bakugan. During the battle, Mira seems to be purposely losing. Baron, Shun and Marucho have beaten the other Vexos and arrive in time to see Dan and Ace win, claiming the mechanical Maxus Dragonoid traps.(Baron beats Volt; Shun & Marucho beat Shadow and Mylene). Spectra is furious at Mira's betrayal, claiming that they have even stronger bakugan than the ones Gus and Mira used. Mira apologizes for betraying the Resistance, but they welcome her back into the group otherwise. They next head to the Vestal Palace to free all the original Guardian Bakugan and save New Vestroia for good.

With Mira returned, and the Resistance reunited, Dan and the others head for Prince Hydron's sky palace to free Skyress, Tigrerra, Preyas, Gorem, and Hydranoid from captivity. But before they can even get close enough, Hydron activates another dimension controller, causing the Bakugan to turn back into ball form. Quickly thinking, Shun grabs Mira and Marucho and grapples onto the top of a rising elevator and to safety. Down below, Dan, Baron, and Ace are saved just in time by their Bakugan. But before they can think of a way to get up to the palace, Spectra and Cyber Helios challenge them to a battle. As Dan and Drago struggle to fight back against the power Helios now possesses, Shun, Marucho, and Mira have managed to sneak into Hydron's throne room and discover the bronze statues of the five other Guardian Bakugan, just before meeting face to face with Prince Hydron himself. Meanwhile, Mylene, Volt, and Shadow order Dr. Clay to give them an escape off of New Vestroia, as the energy from the battle between Cyber Helios and Drago could destroy everything around them. Dr. Clay at first refuses saying that it would be treason, when Shadow reminds him he works for the Vexos now. Gus overhears their plan, but before he can warn Spectra, Lync hits him over the head and knocks him into a room, locking Gus inside so he can't tell Spectra of their plan. Back with Dan and Drago, Spectra, having underestimated the perfect core's power, has used the mechanical Bakugan he has to make Maxus Helios, a Bakugan who has all six attributes. Dan tries to use a combination of Ability Cards that tap into the Perfect Core's power, but still can't match Maxus Helios's power. Dan realizes he has no choice but to use the Bakugan he got from his battle with Mira to make Maxus Dragonoid, just as Spectra has again used the other six mechanical Bakugan on Helios. The two Bakugan face each other, preparing for the final battle.

As the battle between Maxus Drago and Maxus Helios rages on, Mylene interrupts Hydron in his collection room by dragging him off. She explains that they are leaving New Vestroia. Hydron refuses at first, being afraid to face his father due to his failure to successfully occupy New Vestroia, but agrees to Mylene's plan to label Spectra as a traitor. Meanwhile, Mira, Marucho and Shun try to activate a machine to reverse the process of Preyas, Gorem, Tigrerra, Hydranoid and Skyress's petrification but are unable to determine the numeric code. Dan and Drago take to the skies to battle Spectra and Helios but the power coming from their battle is far too much and they crash into the palace. Mylene prepares for their departure from New Vestroia but not before tossing out Elico and Brontes, believing that Bakugan with feelings are useless and imperfect fighting machines, since Dr. Clay has already created many powerful mechanical Bakugan. Out of a stroke of luck, Elfin discovers the activation code, but with the palace self destruction under way it may be too late.

As Dan and Spectra continue their battle, and the self destruct sequence begins counting down, the rest of the six fighting Bakugan are freed from their prisons. As Shun and Marucho are reuinted with Skyress and Preyas, the Bakugan in Dan and Spectra's battle suddenly return to ball-like states, and the battle ends in a tie. But CyberHelios wants to continue fighting, even if the battle is over. Cyber Helios and Drago engage just as Ace and Baron, riding on Percival and Nemus, meet up with Shun, Marucho, Mira, and the rest of the six fighting bakugan. As Cyber Helios and Drago battle, Spectra draws a blade, and forces Dan to battle him one on one. Before either battle can reach a conclusion, the Vestal palace explodes, barely giving Dan and Drago any time to escape as Spectra and Cyber Helios retreat with Gus, Brontes, and Elico (whom were thrown out of the escape craft by Mylene). Gus immediately informs Spectra that the others left New Vestroia to blame the occupation's failure entirely on Spectra's betrayal. Spectra merely states that he never really planned on returning to the Vestal home world anyways. Meanwhile, the Resistance celebrates their victory of liberating New Vestroia and freeing the bakugan. Mira, Ace, and Baron decide to return to their world to prevent the Vexos from ever returning to New Vestroia and enslaving the Bakugan again. The others decide to return to Earth with their Bakugan and the original fighting Bakugan, but Skyress declines the offer, saying that she can't bear to leave her home again and that Shun's future lies with Ingram. Right after Skyress leaves, Drago and Dan regrettably inform Marucho and the others that Drago cannot leave New Vestroia, as the Perfect Core is a part of him. But then Apollonir and the rest of the legendary soldiers appear and grant Drago freedom to live wherever he pleases, with the ability to go back and forth between the worlds as he wishes. With that, Dan, Marucho, Shun, and the rest of the Bakugan return to Earth. Various portals open up across the world, allowing Alice and Julie to reunite with their Bakugan. Dan arrives at Runo's family's cafe and tells her New Vestroia has been saved. Just as he believes Runo is about to run to him, she scoops up Tigrerra, reunited with her Bakugan as well. Highly embarrassed, Dan yells at Drago to never speak of this again. Marucho and Shun walk in with their respective Bakugan, and Julie joins the group shortly afterwards. The Bakugan Battle Brawlers are back together again.