Tanks But No Tanks (Atari 2600)

As the lone defender of the last remaining outpost, you are under attack by an overwhelming force of mysterious phantom tanks that disappear and reappear at will while destroying all that stands in their way. Your vital mission is no simple task - defend the outpost and destroy the enemy as they advance relentlessly through your defense mazes. Only brilliant strategy, perfectly executed, can save you - and the free world!