Robot City (1983)

Robot City is a maze shooter. The player controls a robot trying to destroy the Andromeda robots inside a maze. The Andromeda robots have force fields and can only be destroyed by being shot in their backs. They only shoot forward, and will do so whenever the player crosses their line of fire, even when walls are in the way. If the player manages to make two Andromeda robots destroy each other, bonus points are awarded (25 instead of the usual 10 for destroyed robot). The player is killed whenever hit by enemy fire or colliding with the Andromeda bots (or their remains, when destroyed). After killing all four robots in a level, the player progresses to the next, more difficult, level.