The Blood Pact is a highly organized Chaos warrior-cult devoted to Khorne. Unlike many Chaos cultist warbands, the Pact fights as a disciplined army, and this is what makes them so effective compared to the disorganized Chaotic masses. Consisting of highly trained, vicious soldiers and alien mercenaries, the soldiers of the Blood Pact know no fear or hesitation. They have overrun entire worlds and caused the people of the Imperium no small amount of suffering and woe.

Blood Pact warriors usually resemble a particularly ragged or barbaric regiment of the Imperial Guard. They wear fabric battledress uniforms either looted from the corpses of Guardsmen, or manufactured to resemble a basic Imperial design. Over this are worn packs, webbing and the usual assortment of infantry kit, including a steel bowl-helmet. Because their kit, equipment and battle dress is essentially a mix of plunder and homemade, no two Blood Pact troopers are ever identical. Their appearance is rough and ill-kempt: their clothing torn, patched and dirty, and helmets chipped and dented.

A Blood Pact member is most characterised by their ritual iron visor, known as a grotesque, and which is worn by all human members. These generally portray a grimacing, or leering face, often coupled with an exaggerated hooked nose or chin. These masks are usually a black colour, although it has been known for senior officers to wear one of gold or silver.

Their armour and clothing is all a drab red, the colour of dried blood. In fact, one of the Pact's rituals prior to battle is to dye their clothing with the blood of their enemy. As a result, the Blood Pact warriors exude a revolting, charnel stink, made even less palatable by the unguents and oils with which they anoint their bodies and their own lax standards of hygiene. Their support vehicles all tend to be painted this universal crimson as well.

A Blood Pact warrior's hands always remain bare to display the ritual scars across the palms and knuckles, made at the time of induction to the Pact. Often this ritual scarring covers other parts of the body and face. The deeper and more severe the wounds, and the amount, are part of a unofficial honour system and devotion to Khorne.