Tac/Scan is a 1982 space combat shooter video game originally released as an arcade game, and later ported to the Atari 2600. It was developed by Sega Electronics (formerly Gremlin Industries) and published by Sega of America.
The game was notable for its 3D vector graphics that switched between an overhead and third-person perspective, and for its tactical elements, putting the player in command of seven units in squadron formation through waves of attacking enemies; the player can gain reserve units, while being able to command the units to perform various actions, including firing at enemies, getting into formation, or a “tac” maneuver.
Tac/Scan is a unique game in that the player controls just how many resources (in this case, ships) are put into play. The game starts with seven individual ships in play. Those ships can be lost in any of the three stages by hitting a tunnel, getting shot, or colliding with an enemy, the laser-firing Ahmins composing the superfleet from the planet of Ahm. The player is able to “collect” and earn these ships back as the game progresses. The squadron can drop down to one ship in the game, but still have four “back-up” ships. If the final ship in play is lost, however, the game is over. This is different from other games that give the player ships sequentially.