Descent is the third and final chapter of the Alien Breed: Evolution series. The player commands Chief Engineer Theodore Conrad from the alien-infected ship Leopold as he descends into the alien ship that started this whole mess to find out the secret behind this Alien Breed once and for all. The game plays as a standard twin-stick shooter, pitting a single character against a massive alien horde with scarce weapons and having to pick up supplies on the way. The levels are available as singleplayer Story and Survival modes, as well as multiplayer cooperative games.
The third part brings a number of additions to the series like new weapons, alien types and special third-person sections in the campaign.