just a lot but i'll pick what stands out in my mind,
beat-em-up:
D&D shadow over Mystara, like, this game is practically the inspiration of Dragons Crown
Simpsons arcade, it's so good especially with 4 players.
the Punisher, about the only beat-em-up with guns you can use.
Alien vs predator
battle curcuit
armored warriors
michael jackson's moonwalker
ninja baseball bat man (if that TITLE doesn't make you look this up, idk what will LOL)
King of dragons
knights of the round
Three wonders, a capcom arcade game 3 entirely different games, mystic wanderers is like sorta metal slug contra ish, Chariot a side scrolling shooter (horizontal) and don't pull an action puzzle game
puzzle games:
battle balls
puzz loop
Columns
Mr driller (any of them), cause damn i find it super addicting in every title.
magical drop games, really unique in it's gameplay in my opinion
puzzle fighter 2 turbo, it's quite fun in versus modes, crazy chains and such.
block out, (3d tetris from top view)
Shoot-em-ups:
Ikaruga, the mechanics get wild and most unique of all shoot em ups i've seen.
radiant silvergun also, which is sorta a prequel to this.
gigawing, shootemup with reflecting bullet with your shield when the gauge is up,
gigawing 2 is imo a better game but only on dreamcast , not arcade
Varth operation thunderstorm
Un squadron, and carrier airwing, horizontal shooter with buying weapons between levels.