When Batman was only 10 his mother and father were killed by a super villain call Metal Claw. He swore revenge on him and trained for years. In 2 ABU he became rivals with Superman and they fought over who was the best superhero.
In 7 ABU Batman and Superman tracked down Metal Claw to Rainbow land. However when they got there everyone had been killed except Unikitty, Princess of Rainbow land. Unikitty helped Batman defeat Metal Claw.
Professor Arachni Edit
In 9 ABU Batman and Unikitty had tracked down a villain called Professor Arachni. When they arrived to confront him they found Agent 10 and helped him chase Arachni away.