The levels in Planet Strike are called Areas. Planet Strike is divided into 24 areas, 4 of which are secret levels. The player's main objectives in each area are to find the fission detonator and use it to destroy the security cube, unlocking the teleport to the next level. Unlike in Aliens of Gold, the game is not divided into separate missions. In the game engine, areas start at 0, so area 1 is 0, area 2 is 1, and so on.
A map of all areas is shown on the teleport control panels. The shapes of the areas on the map, however, do not represent the actual shape of the levels (all levels are essentially in a fixed square area). Likewise, the locations of the areas on the main map also do not represent the actual locations of the levels, the levels being separate unrelated maps.
12: Cryogenics Labs
17: Crew Quarters
20: Goldfire's Lair