Gruul Goblins is a fast red aggro deck, so Hydroblast is excellent — it counters or destroys their Lightning Bolt, Incinerate, and other red threats/spells cheaply. Annul can strip Powder Keg-adjacent artifact threats only if relevant, but here it mainly answers nothing key since Goblins run few artifacts/enchantments; consider it a marginal include for flexibility against Cursed Scroll-type plans in other builds, or cut it back if unneeded. Board out slower interaction like Daze (weak once they're ahead on board), Thwart, Misdirection, and Peek in favor of proactive red-hate. Prioritize surviving the early rush with Stifle/Vision Charm still available to blank Dreadnought irrelevant here, and stabilize with card draw.