When I was a kid just discovering Guns N' Roses, I always pretended to be Slash while reenacting the music videos I saw on MTV. Maybe a part of me could sense that one day Axl would swell with both girth and wackaloonitude, or maybe I just admired the pimp daddy top hat and undeniable skill. Regardless, Slash was, is, and probably always will be the man.
As I grew up, though, I started to see the name Slash a lot in my video games. That's not so surprising, of course. It's a cool name, perfect for any random blade-based character, and lots of time that's all it is. Then again, sometimes it's because there are a lot of G N'R fans out there making video games, and they share my affinity for the guitarist.
Capcom's Final Fight is still the template for the perfect sidescrolling beat-'em-up. It's also famous for having one of the first openly transsexual characters in video-game history. Capcom USA balked at having the male protagonists beating up the female character of Poison, to which series creator Yakira Asuda replied that all was cool, the character was actually a transvestite. (Apparently beating them up is perfectly fine.) The official American stance is that Poison is a post-op transsexual. Also, about that name...
Many of the Final Fight characters are named after bands and musicians, including Slash. A large, imposing man with curly hair and dark skin, he's a subordinate of the international terrorist Rolento. He's he only character in the game who can block attacks, and his strikes do almost as much damages as the bosses.
Sega's attempt to cash in on the fighting-game series was Eternal Champions, and it wasn't really all that bad. The premise was that the souls of great warriors from across time had been snared in order to participate in a tournament that would allow the victor to change their fate and avoid their death. Think of it like Time Killers, but less ridiculous.
One of the characters available was a caveman named Slash, and while other chacracters were masters of various martial arts like Savate or Hapkido, Slash's discipline was simply listed as Pain.
It's purely fan conjecture that Slash was named for the guitarist, but, the curly hair, wide nose, and deep-set eyes do bear a pretty sharp resemblance. There's also the matter of Slash using a club rather than the bladed weapon you'd expect with the name.