Serpento

Serpento is a snake game with a twist: eating every apple is only half the job. Once the board is clear a door slides open in the wall, and you have to lead your whole tail out through it to finish the level. 24 stages run from open fields to tight two-tile mazes, with pits that teleport you across the board and frogs that hop away as you close in. Three speeds, four control schemes, a best score kept for every level.