Dragon Claw by Reuben Kee

then it all completely breaks down after that but these are other characters that come in mind and their reason why
Kung Fu Man by Elecbyte (first character in mugen)
Mario by ShinRyoga (classic character)
Princess Peach by EugeneQ (cute sprites and character)
Riesbyfe Stridberg by IQS (has an AI patch that competes with Dragon Claw, entertainment value)
Blackheart by Cyanide (Carbuncle AI patch and my favorite MvC character)
Arle by M3 (Idk why but this character is kinda my official online avatar)
Hotsuma by @Varia31 because he needs to make him a character already lmao