treasure was a third-party game developer that occasionally did work for first-party companies such as nintendo and sega. most of their work is phenomenal, and a lot of it is well-remembered, but it still feels like they, as a developer, are underrated. if you've ever heard of gunstar heroes, radiant silvergun, or ikaruga--that's treasure.
personally, my favorite title of theirs is dynamite headdy, an offbeat platformer for the sega genesis that sported a kind of puppet show theme.
it had an interesting gimmick in the form of headdy's changing heads. you could pick up powerups like a vacuum head that sucked up all enemies on screen, a hammer head that turned headdy's regular head toss into a stronger attack, or even a small head that turns his entire body small. the game got really creative with its head-swapping concept, as well as other gimmicks involving the use of headdy's head-toss. it's aged really well, and is still worth playing today! but play the japanese version with a translation patch if you can; the international release cut out most of the dialog and generally made the game more difficult.