Leon (Final Fantasy II)/Opera Omnia

Leon is quickly brought under the sway of Emperor Mateus after arriving in the new world. Mateus manipulates his desire for power and orders Leon to attack Firion and the others of Mog's group. The ensuing battle snaps Leon out of the mind-control, and Irvine drives Mateus away. Horrified by his actions, Leon attempts to leave, but the others call him back insisting that they do not care about his past misdeeds so long as Firion considers him a friend.

Nevertheless, Leon is still troubled by the thought that his desire to become powerful could leave him open to the Emperor's brainwashing again and bewildered that he's been so readily accepted as an ally despite his actions. Seifer snaps at him, calling him a "dark-wuss" whose interests only happen to align, and says he should just do what he wants the way he wants to. Despite the insulting words, Leon finds some measure of conviction in this, and Firion assures him that they will set him back on the right path should he stray.

Leon, apparently not traveling with the group full-time, trails them in the World of Darkness as they traverse Pandaemonium. He appears just in time to confront Mateus with them and saves the party when the castle destabilizes due to the numerous portals the Emperor has attempted to open to other worlds. The party escapes through the Torsion that Leon opens. However, he does not join them when they exit, preferring to remain separate for reasons of his own.