Orzhov Amalia wins by chaining small lifegain triggers from creatures like Haliya and Hinterland Sanctifier to grow Amalia Benavides Aguirre, while Starscape Cleric turns each of those triggers into life loss for you. Pyroclasm is strong at sweeping their low-toughness value creatures before Amalia gets out of hand. Abrade's 3 damage answers Amalia herself (you'll have to pay 3 life for her ward) and most of their other creatures cleanly. Sear and one Impractical Joke come out since they're less efficient against this swarm of small bodies compared to Pyroclasm's one-sided-ish sweep. Prioritize killing Amalia or Haliya on sight since the lifegain engine compounds quickly if left unchecked.