Engineered Plague chosen for Goblin shuts down their entire tribal synergy suite (Goblin Piledriver, Goblin Warchief, Goblin Ringleader, token Goblins from Siege-Gang Commander) by giving them all -1/-1, killing the 1-toughness Mogg Fanatic and Goblin tokens outright. Infest sweeps their small creatures (mostly 1/1s and 2/2s) for -2/-2 without hurting your bigger threats as much. Phyrexian Furnace is weak here since this Goblin build has no meaningful graveyard recursion to disrupt. Wrath of God and Bane of the Living remain excellent since this is a low-toughness aggro swarm deck that folds to sweepers.