I see Metal Slug, Terranigma, Capcom vs. SNK (The NeoGeoPocket version), WakuWaku 7, I think there might be a couple Tales of Phantasia sprites...Puzzle Fighter/Pocket Fighter sprites...Oh, Roomi from Galaxy Fight...Boogerman....(I'm ashamed I know that game)...Hah, Teyandee Kyatto Ninden! Viewtiful Joe....Wonder 3? Capcom game at any rate..arcade. Guys in the upper right corner, upper left corner and lower left corner.
I think there might be some from the Knights of the Round Table arcade game too, also from Capcom.
Also, there's a lot of repeated characters. I counted no less than three Eggmans and two Shermies.
Okay, with a little more examination, I've found, in addition to those tagged and my list above...
Bomberman, a sprite from Ogre Battle, Willow (Arcade game), there's *definitely* Tales of Phantasia sprites, Toejam 'n' Earl, Kieth Courage in Alpha Zones, Megaman, Super Mario RPG, Secret of Mana, some sprites from Capcom's Marvel games (Either Marvel Super Heroes, Street Fighter vs. MSH, Marvel vs. Capcom...one of 'em), Twinbee, Earthbound, hey, Strider, Final Fantasy...3 and 6, and several games I recognize but don't know/remember the names of.
