Thunder Warriors were large, greater in size than most [[Space Marine]]s. In their earliest days the Thunder Warriors wore metal armor with leather strappings and wielded [[Lasgun|Lasrifle]]s.{{Fn|10a}} 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. Even severely deteriorated Thunder Warriors shown capable of fighting multiple Astartes at once.{{Fn|5b}}{{Fn|8}} They were made highly resistant to psychic attack, perhaps because of the sorcery they would regularly face during the [[Age of Strife]], with any attempts at mental attack causing severe pain to the psyker.{{Fn|8}} 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}} Their reflexes were also extremely enhanced, allowing a Thunder Warrior to dodge the shot from a plasma gun, while already engaged in and focusing on fighting two other Astartes.{{Fn|8}} The Thunder Warriors genetic template was unstable and they were prone to fits of bloodlust and instability. Short-lived and rife with both mental and physical health issues, Thunder Warriors were known to suddenly drop dead or stop following orders.{{Fn|10a}} Unlike the later Legiones Astartes, they lived as warlords and relished battle. Their human emotions were not expunged from them, and they were known for their dry humor.{{Fn|10b}}