Thunder Warriors were large, greater in size than most [[Space Marine]]s. Despite physical deterioration, the few Warriors that survived the end of the [[Unification Wars]] were easily more than a match for an Astartes, and had even outperformed [[Custodian]]s during combat engagements. They were made highly resistant to psychic attack, perhaps because of the sorcery they would regularly face during the [[Age of Strife]]. They had tremendous upper body strength that was considered to be unparalleled, which, when coupled with their early model of [[Power Armor#Mark_1_.22Thunder_Armour.22|power armor]], made them virtually unbeatable in close combat.{{Fn|2}}{{Fn|5b}}{{Fn|8}} The leg strength of even a heavily physically deteriorating Thunder Warrior made them capable of kicking completely through the torso of a normal human.{{Fn|8}} Their bones were thicker than that of an Astartes, with a Thunder Warrior capable of shattering the skull of an Astartes with a headbutt.{{Fn|2}}