Single-Player 
Excubitor is a tower defense shooter game developed by Tesseract Interactive that is available for purchase on Steam for PC, Mac, and Linux. Over a century from now mankind will be plunged into an interstellar war over the existence of a new resource, called Voidshards. The mothership houses much of humanity as they travel throughout the vast regions of space, searching out these Voidshards, but they are not alone. Fierce enemy drones are approaching the mothership at a staggering rate and trying to bring it down. The only thing standing between these unknown enemies and the mothership's utter destruction is you, the turrets you construct, and your trusty defensive ship, the Hammerhead.
Features:
Hammerhead Abilities: Give the Hammerhead new abilities like shockwave and berserk to make quick work of your enemies.
Turrets: Build different kinds of turrets like the Prism turret or Gatling laser turret to defend the mothership. After all, you can't be in every place at once!
Varying Difficulties: Play through four types of increasing difficulties, including NewGame+ which is the hardest of all the difficulties and gives you the chance to use some special weapons.
