Lyon vs N (Fire Emblem vs Pokemon)
(I haven't been active for a while, so I dunno if this is gonna get deleted, so I'll just post connections anyways)
Goodhearted young men at heart, these princes are forced against their better nature to a position that will ultimately bring ruin to their worlds. However, in their zeal and delusion, they firmly believe that they are in the right -- that their actions will better the world, either by saving the lives of many, or freeing those shackled to the whims of another. They invite the protagonist -- one with conflicting ideals that they wholeheartedly see as their closest friend -- to a final battle to decide all, and in their defeat at last realize the error of their ways, only for those who had been pulling the strings behind the scenes the entire time (Fomortiis / Ghetsis) to reveal themselves as the true evil.
Whereas Lyon perishes, content in his defeat and remorseful for his sins, N instead journies, hoping to come to terms with his own flawed idealogy, ultimately defecting against Ghetsis.