Rampart, produced by
Atari Games, is one of the most fondly remembered
arcade puzzle games. The player must use a crosshair to aim cannons at enemy ships gathering offshore around his island. This much is similar to
Missile Command. But after a short period of time a cease-fire is called, and then the player must use mutant
Tetris pieces to rebuild the wall around castles before the ships start firing again. Failure means the game ends. Success means the player gets more cannons with which to deplete the opposing navy.
Rampart is easy to learn, but has very intricate gameplay, in which every action and choice has a tradeoff of some kind. I consider it to be the best-designed computer or video game ever made.