The screen is broken up into 14 x 13 tiles or checks. When the player passes over the tiles, they disappear so each tile can only be walked over once per level. Some tiles are taken up by skull and crossbones which kill the player if walked into. The skulls turn to time bombs one at a time and the player must walk over them to defuse them before they explode. They must avoid the skulls and make sure they do not block off a possible future route by circling it. Some tiles are also flags which can be collected for bonus points. When all skulls have turned to bombs and been defused, the level is complete and begins again at a harder level. As the game develops, stomping boots are introduced that move around the playing area. These are also deadly to the player.
Ports and clones
The arcade game was relatively obscure and there were no official ports to home systems but there were clones. Danger UXB (Micro Power) for the Acorn Electron and BBC Micro was released in 1983. This was originally named Blockman but the name was changed by the publisher before release. A version called Gridtrap (LiveWire) was released in 1985 for the Commodore 16 and Plus/4, Commodore 64, Amstrad CPC, MSX and ZX Spectrum.