Grixis Reanimator wants to fill the graveyard with Faithless Looting and Thought Scour, then bring back Archon of Cruelty or reanimate cheap threats with Unearth and Persist, plus Abhorrent Oculus needs six cards exiled from the graveyard as an additional cost. Keen-Eyed Curator's repeatable graveyard exile can strip their Archon of Cruelty or Emperor of Bones targets before they get reanimated, and it also disrupts the resources Abhorrent Oculus needs. Six blocks their Psychic Frog reasonably well and can find extra land off its mill. Elesh Norn, Mother of Machines is a big, resilient threat that dodges Fatal Push. Summoner's Pact is unsafe against a deck with Thoughtseize and cheap discard/removal to strand the payment, so we take it out along with some Malevolent Rumble.