Unholy Heat is excellent removal against Ragavan, Nimble Pilferer, Guide of Souls, and Ajani, Nacatl Pariah's Cat Warrior tokens, easily killing all of them and scaling to 6 for bigger threats like Boromir, Warden of the Tower. Surgical Extraction needs a target card in a graveyard, so it isn't a proactive play. Once a Ragavan or another key threat has died, it can exile the remaining copies from their hand and library before they snowball. Thoughtseize is removed because their deck is proactive and low to the ground, making discard too reactive and slow to keep up with their clock. Nihil Spellbomb is also cut, since exiling graveyards does little against them and our own graveyard fuels delirium.