Segua Kingdom has been losing the war against Ninterdo Empire but the tables are turned by the appearance of a boy called Gear. All the characters are parodies of Nintendo or Sega games such as Sonic the Hedgehog, Super Mario Bros., The Legend of Zelda etc.

After returning from the feuding realms of Gundalia and Neathia, Danma Kuusou and his companions continue their lives on Earth. Now, a year later, the virtual reality world of Bakugan Interspace has finally recovered from the alien invasion and has once again become a place for brawlers to gather and challenge themselves. It turns out, however, that whenever Danma's Bakugan, Pyrus Dragonoid, unleashes his might in battle, the Interspace experiences new disruptions. Unable to harness the incredible powers granted to him by Code Eve—the Bakugan Mother spirit—he struggles to maintain control over the Mechtogan contained within him. When it goes out of control, the mysterious mechanical entity wreaks havoc on the battlefield, attacking friends and foes alike. To make matters worse, Bakugan Interspace is at risk of being infiltrated again. An unknown mastermind is sending mutated Chaos Bakugan into the system in order to brainwash brawlers and take control of the virtual realm. In anticipation of the inevitable confrontation, Danma must find a way to keep the Mechtogan's destructive force at bay and rally the Battle Brawlers once again. [Written by MAL Rewrite]

Fourth season of Doupo Cangqiong.

Kaito Daimon would be a completely average high school student except for one thing: he's a 'demon' at solving puzzles. Kaito is so brilliant, in fact, that when he's asked to take some 'special' tests of his unique ability, he immediately suspects that the test itself is a test. Kaito suddenly finds himself caught up in a lethal Philosopher's Puzzle made by the sinister group POG, a murderous maze of trap upon trap, where failing to solve the secret correctly will result in death! Fortunately, Kaito's skills prove up to the first test, both for himself and his childhood friend Nanoha, who is also caught up in the deadly scheme. But now that he has been designated as a Solver, he is pulled into a new life where he must travel the world with other Solvers, attempting to solve the latest deadly riddles left by POG. There's a new conundrum around every corner and each deception could lead to death, but once a riddle has been posed, you can count on Kaito to unfold, unravel and unlock it! (Source: Sentai Filmworks)