Gruul Sligh races with small creatures, Survival of the Fittest as a value engine, and direct burn to close games before your combo assembles — your priority is surviving long enough to resolve Replenish. Seal of Cleansing is your most important card here; destroying Survival of the Fittest cuts off their recursive threat generation with Squee and Arrogant Wurm, so deploy it aggressively rather than holding it for later. Parallax Wave does heavy lifting against their creature suite, and you retain two Decree of Silence for the Wave lock in games that go long. Exalted Angel comes in as a morph on turn two off Ancient Tomb, stabilizing your life total against their burn plan and presenting a win condition if your enchantment combo is disrupted by their sideboard Reverent Silence or Naturalize. Blue Elemental Blast and Hydroblast protect your key blue spells from their Pyroblast package while also being able to counter burn spells in a pinch; Abeyance is cut because it only delays a single turn against a deck full of creatures, and trimming a Decree of Silence and an Opalescence acknowledges the mismatch between those six-mana investments and the speed of this matchup.