Silkworm is a side-scrolling shooter arcade developed by Tecmo and released initially in 1988. In 1989 the game was ported to Amiga, Atari ST, Commodore 64, and ZX Spectrum by Random Access.
The developer of the Amiga version, Ronald Pieket Weeserik, did an excellent job, and this computer version is considered even better than the original arcade.
Silkworm (sometimes written Silk Worm) is a good game played alone, but it's fantastic for two players. The first player controls a helicopter that can fly and shoot in the sky, with a classic "fire and move" gameplay. The second player controls a jeep that cannot fly (of course) but has a turret that can be rotated using the cursor's keys to hit the enemies. Players need to cooperate; each one needs to cover the other to survive the attacks of several kinds of enemies and fortifications. If this was not enough, the background music, written by Barry Leitch, is considered a cult.
Silkworm is fast and challenging, and once you have started playing it, you won't stop quickly!