Monsters is a variant of the arcade game Space Panic. It's a single screen platform game where the player has to kill monsters by digging holes in the ground. When the monsters then walk over the holes they get trapped and the player can kill them by filling in the hole. They will then fall down and die and any other monsters they hit will also be killed. If the hole is not completely filled in the monster will crawl out and escape. There are three different monsters and the differ in the number of levels they have to fall through to die. Red ones need to fall through one level only, green ones two and white ones three. After the first stage red and green monsters that escape from a hole will mutate into green or white monsters respectively. The player also has a depleting oxygen level and a stage has to be completed before it reaches zero.