Spooky Helmet

No piece of this drops finished. The whole set is built out of Spooky Wood, which falls from Pumpkin Moon enemies, so the real cost is running that event well enough to reach the waves that pay. There is a loop in that for summoners: you need decent minions to survive the moon, and the moon hands you the armor that makes minions good. Most players bank wood across several nights in Tiki armor first.

Spooky and Tiki sit at the same tier and pull opposite ways. Spooky pushes raw summon damage far higher, so it wins for anyone who plants minions and then concentrates on dodging. Tiki wins if you are actually swinging whips, since its reach changes how close you have to stand. The movement speed on the legs matters in moon event arenas, where you run laps all night.

The bonus multiplies with accessories rather than sitting on its own. A Papyrus Scarab, a Hercules Beetle, the Summoner Emblem and a Necromantic Scroll together lift minion output well past what the armor manages alone. Pair that with the Tempest Staff or the Deadly Sphere Staff at this point in a run.

You will end up with far more wood than a set needs. Crafting helmets and selling them is the most efficient way to turn the surplus into coins, since the helmet returns the most per unit of wood spent. One cosmetic note: the orange markings vanish while the Moon Lord's screen distortion is up, so do not panic when the armor goes plain mid fight.