Necrons are artifact creatures introduced through Magic's Warhammer 40,000 Commander decks. Their cards heavily emphasize artifacts, graveyard recursion, self-mill, and mechanical armies that have an inconvenient habit of getting back up after getting knocked down, “Tubthumping”-style.
Imotekh the Stormlord creates additional Necron Warriors when artifacts leave your graveyard, while Trazyn the Infinite borrows activated abilities from artifact cards buried there. Living Death provides an appropriately dramatic way to awaken an entire Necron tomb.