4c HollowOne dumps its hand fast with Faithless Looting and Burning Inquiry to cheat Hollow One and Vengevine into play, so Erode gives us clean, unconditional removal for their discounted threats. Surgical Extraction can strip a copy of Hollow One or Vengevine from their graveyard and library after they discard the first one, slowing down their recursive threat generation. Thraben Charm's damage output scales with our creature count and can be too slow against their explosive starts, while Dalkovan Encampment is too passive against an aggressive graveyard deck, so both are trimmed for more targeted answers.