What it does
"Primarch of the Death Guard" isn't actually a keyword or ability—it's the title/subtype reference for Mortarion, Daemon Primarch of Nurgle, a legendary creature from the Warhammer 40,000 Universes Beyond Commander decks. Mortarion himself is a 6/6 flying creature whose ability lets you sacrifice creatures or artifacts when he attacks, dealing damage to each opponent equal to the toughness sacrificed, then returning those cards from your graveyard at end of combat.
The common confusion: there's no game keyword called "Primarch of the Death Guard"—people sometimes mistake flavorful card titles for mechanics. Mortarion's real engine is recurring sacrifice fodder for repeated value and reach.
In Commander, he anchors aristocrats/reanimator strategies. Pair him with high-toughness creatures or sac-payoff engines (Blood Artist effects) so each attack drains the table while you rebuild your board for free.
Iconic cards with Primarch of the Death Guard
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