Considering most goblins have haste or you can at least give it to them, Wort offers a great way to keep the board full and your threats ever-present
Bolass Crimped Citadel Crimped cards are already fun, but this one has the crimp in a really unusual spot
Kros gives you two abilities
Then the three-drop enchantment in Black will in your upkeep toss two counters here and then mill that many counters in cards, great over time
If the spell is an instant, you can cast it at instant speed, and for sorceries you can only cast it for its flashback cost at sorcery speed
Even if the Curtains die to a Lightning Bolt or Unholy Heat (rarely with delirium on Turn 2) after blocking the Monkey, they still blocked the Monkey before trading, when the typical auto-loss pattern is having your Turn 1 creature die to removal on the spot while your opponent gets a free Treasure and card flip