Gate Defender

Tower defense above the planet

Gate Defender is a first-person tower defense game for PC. Balloons carrying blight travel along a route across small islands in the sky, heading for the Gate, a machine that leads down to the planet. You build defenses to stop them, then fight alongside your towers when each wave begins.

The campaign spans eight worlds across the solar system, with three maps per world. Each map has its own terrain, sky and rule that changes how you defend the route. Clearing a world opens the next one.