Zap | Classic retro game for the Commodore PET Computer (1978)

ZAP is an implementation of the well-known Snake game where you steer your snake around the screen and eat the blocks littered around the playfield. Every time you eat a block, your snake gets longer. Crash into a wall or your own tail and you lose. Control your snake with the number pad.

The flyer claims that the player is controlling a strange missile but we all know it's a snake. There's no special character denoting the head of the snake, so in the screenshot, you can't tell what direction it is moving.