Hridgandr is a metal mace with retractable spikes, and the weapon of choice for Hogun, a member of the Warriors Three.
Believed to be Asgardian in nature, this mace was used in battle by the Vanir Hogun. The mace has retractable spikes, making it an extremely deadly, if not crude, weapon.
Hogun used his mace in the brief bout against the Frost Giants on Jotunheim, then again against the Destroyer on Earth. 
Hogun took part in the battle against the Marauders across the Nine Realms, once again armed with his mace.