The single-player only game features a branching campaign of repetitive missions where you must design a ship to defeat a series of enemies followed by the last ship you designed. Components for the energy core, crew, hull, engine, wings, weapons, and other accessories can be freely attached, scaled, or rotated in 2-D. Controlling the ship is performed using the WASD keys. While the crew automatically fires weapons, camera control is very inconsistent and it is difficult to aim precisely. You can take direct control of a component to repair it or improve the stats, but this usually leaves the ship vulnerable in other aspects. Scrap dropped by defeated vessels can be used to repair. AI ships is good enough to act as capable adversaries. Although Defect has a very novel concept, monotonous mission design and a cumbersome control scheme reduce enjoyment.