Mushroom Roulette is a simple puzzle game, and like all good puzzle games, comprises a handful of elements, with levels ringing the changes on what's feasible with those elements.
You control a single character with the arrow keys; scattered about the screen are red mushrooms, which earn you both score and health, and you must eat them all to complete the level. There are also sliding blocks, leading to Sokoban-style puzzles, as well as inert ones; purple mushrooms allow you to destroy a block, while black ones freeze all in place. Pink mushrooms give score but cost health, and there are also butterflies, mobile enemies that will cost both health and score. However, after eating a purple mushroom you can eliminate one instead of a block. Hats protect you from butterflies (once), but if retained increase your score as well.
The game contains two progressions -- the "normal" levels and the "map" levels -- as well as randomly-generated levels, which are less interesting. A separate level editor is downloadable, and the game is technically donationware, although the author invites level contributions and/or ports to other platforms as constributions. (He has versions available for Dingoo and the GP2X, obscure Linux-based handheld consoles, as well as for PC at present.)
By default, the game plays in a tiny 320x240 window, although there's a .bat file that will start it in full-screen mode.
While the gameplay is quite good -- reminiscent of the DROD games, though not as polished -- the game does not, awkwardly, allow you to save your progress through either of the two progressions, so that you must start with the first level of each on a subsequent play. Still, it's fairly entertaining.