The first one that came to mind was Ripper Roo.
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First creepy-lookin', crazy-laughing, bomb-throwin' lunatic of a looooooong series I've encountered, and he remains one of my all times favorite to this day.
Then there's Prometheus.
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Really enjoyable to fight, love his sadistic personality, and he actually says really deep things - about as deep and sad as his backstory. Two others from the Megaman series would be Bass.Exe
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and Dynamo
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Finally, I'mma end this list with... Yeah, she's definitely in my top 5 favorite character, probably even above Ripper Roo. I just think of the crazier ones first. But here we go:
Razzy from Summon Night: Swordcraft Story. I love her and the game she appears in with a burning passion.
