Dimir Control's clock relies partly on graveyard-fueled threats like Gurmag Angler (delve) and Ninja of the Deep Hours triggers, and Tormod's Crypt can strip their graveyard to blunt Gurmag Angler's delve cost, though note it does nothing against their Spellstutter Sprite or hand-based plays. Annul is mostly a sideboard hedge against their few nonland artifacts (Contaminated Aquifer isn't an artifact, so Annul has limited targets here) — consider this a lower-impact include, but their deck runs almost no artifacts or enchantments, so weigh cutting Annul back if you find better options; still, it's a reasonable speculative slot. Fiery Cannonade has few good targets against their small creature suite of 1-3 toughness fliers like Spellstutter Sprite and Faerie Seer, so trimming it slightly for grindier tools is reasonable. This is a long, grindy control mirror where card advantage engines like Lorien Revealed and Murmuring Mystic are premium — protect them with Counterspell.