Orbital Defense

Orbital Defense is a neon tower defence set on the outer ring of a deep-space station. A walkway runs out of an airlock on the port side, past a reactor core, a hangar bay and a hydroponics dome, and ends at the blast door of the bridge. Nine glowing hexagonal pads sit along it, and what you bolt onto them decides how far the machines get. Through the window band above the deck a planet turns, freighters slide by, and the light strips in the floor pulse the whole time.

Five turrets, three marks each. Laser turrets fire a fast beam and are the only thing besides the flak cannon that can touch anything in the air. Flak cannons throw bursting shells that only arm against flyers, so they cover the straight line the drones cut over the deck. EMP coils arc between three targets on the ground, slow whatever they hit, and strip an energy shield the instant they touch it. Missile pods send homing warheads into a crowd and splash everything nearby. From wave six you can raise a drone bay, which launches two or three escort drones that circle the deck and harass whatever comes close.

Crawlers come first, then scout drones that fly the shortcut, shield bots behind a blue bubble that has to break before anything else lands, welders that patch the pack back up, hover tanks that soak damage and interceptors that sprint. Every fifth wave a mech walker stomps in and puts a turret offline with a missile barrage, and wave fifteen brings the Dreadnought, a flying flagship that keeps dropping fresh drones out of its belly. Credits come from kills and from clearing a wave, calling the next wave early pays a bonus, and any turret sells back for sixty per cent. Twenty points of hull integrity, three stars for a flawless defence, and an endless run with scaling waves once the ring still stands.