Adder Attack is a simple arcade game where the player must collect golden nuggets while avoiding deadly snakes. A particularly dangerous blue snake also moves around the screen collecting nuggets. If it reaches the player, it will eliminate them. However, this snake carries valuable opals and occasionally drops one. The player can collect these opals for an extra 100 points.

The game features simple controls using only four keys for movement. The graphics are 2D, reflecting the style of early ZX Spectrum games.