S.I.M.I.S. stands for the names of the games and items on the card. They are SnakeByte, Invaders, Mines, Isolation, and Specials, which are the demos.
The story of SnakeByte revolves around a snake that must navigate the screen without touching the walls or its own body while eating apples. Each apple consumed increases the snake's length, making maneuverability increasingly difficult. In later levels, additional objects appear on the playing field to avoid.
Invaders is a port of the classic game Space Invaders. Players control a cannon at the bottom of the screen, moving left and right to shoot down rows of invaders. The invaders move in a coordinated manner across the screen, with some occasionally dropping down from the top to move towards the opposite side.
Mines is similar to Minesweeper. The player must navigate a room, from the upper left to the lower right, avoiding hidden mines. A mine detector allows players to identify the location of nearby mines, while a detonator enables them to destroy those mines one step away.
Isolation takes place in an eight by six tile area, where players move one step at a time, removing a tile from around themselves. The game alternates between two opponents until one is left with no moves, resulting in loss.
Specials features four playable demos developed by the authors, serving as a preview of upcoming games.