Arcadia combines elements of Gorf and Galaxian. The player controls a space ship as the aliens scroll and moved freely down the screen. The game consists of 12 different levels of descending aliens. After level 12 the game loops back to level 1 with no extra difficulty. An extra life is rewarded after every four levels. Advancing to the next level involves staying alive until the timer in the top left corner ticks from 99 to 0. Once zero is reached the surviving aliens descend rapidly down the screen.
Points awarded per alien destroyed are in line with the current level: Shoot down an alien on level 1 and you are awarded 1 point, roll around the levels and the same alien killed on level 13 is now worth 13 points.