This is a fast mirror-style aggro matchup where both decks are racing, but Goblins has superior synergy through Goblin Warchief, Goblin Ringleader, and Goblin Piledriver threatening to go wide quickly. Pyroclasm and Simoon come in as sweepers to break up their board before Piledriver and Siege-Gang Commander can take over — Simoon in particular hits Goblin Lackey, Mogg Fanatic, and Goblin Tinkerer for a single mana. Rancor and Seal of Fire are the weakest cards here: Rancor requires a creature to already be winning and does nothing against their board presence, while the extra Seal effect is outclassed by mass removal. Keep your burn spells pointed at their key threats — Goblin Lackey on turn one must die immediately, and Goblin Warchief needs to be answered before it accelerates their clock, leaving your Grim Lavamancers and Mogg Fanatics to trade efficiently.