The Bilskirnir-class, also known as an Asgard mothership, was a series of spaceships used by the Asgard at the height of their power. Bilskirnir-class motherships were the primary type of ship used by the Asgard. They had a distinctive shape with a hammer style front with wings by the side and a grayish hull. The sensors of these ships were quite accurate and capable of detecting movements within the vessel should intruders board the craft. This included a type of thermal sensor which allowed for the detection of warm blooded organisms moving about the ship in case the primary internal sensors were disabled. They were used by the Alliance of Nations