Frost Moon

A Naughty Present starts the Frost Moon at any point after dark, and it runs until dawn. In that window you have to push through 20 waves. It borrows the Pumpkin Moon's structure and then makes every number harsher, and from wave 15 onward it puts three boss-class enemies on screen together. The present's ingredients require a post-Plantera world, which tells you the power level it expects, and none of it scales down if you summon one early.

Each kill is worth points and each wave has a score to reach. Hit it and the next wave opens with your score back at zero. Reaching wave 15 costs 3410 points across the night, and clearing all twenty costs 10160. Expert worlds double every point value and master worlds multiply by two and a half, so a harder world is genuinely faster to climb, not slower.

The clock is the real opponent. Dawn at 4:30 AM ends it whether you were on wave 4 or wave 20, and dying costs you only the walk back.

There is a cap on how many event enemies can exist at once. Every enemy still alive is a slot not producing points for you, so the fastest runs delete things immediately rather than doing enormous damage to one target. A weapon that hits a wide area often will out-earn a slow heavy swing here even when the swing looks better on paper.

Present Mimics are the exception to watch for. They can replace a wave-appropriate spawn at any point as long as fewer than four are already out, and they hit hard enough to end a careless run in the low waves.

Everscream, Santa-NK1 and the Ice Queen first appear in wave 4, and at that point their drop chance is about one in nine on classic and one in five on expert. It climbs on a curve from there, reaching roughly a third by wave 19 on classic and certainty by wave 14 on expert. A run that stalls at wave 10 is not worth half of a run that reaches wave 18, it is worth far less than that, which is why the whole event is really a race to build score early.

Trophies roll separately, starting at wave 15 and improving again at 17 and 19. Luck shifts the general drop chance but leaves trophies alone. The Razorpine, Blizzard Staff, North Pole, Snowman Cannon, Chain Gun, Elf Melter and Reindeer Bells all sit behind that curve, so plan on several full nights rather than one lucky one.

• Ichor is the standard opener. A Flask of Ichor, ichor ammunition or the Golden Shower strips defense off almost the entire roster.
• A Warmth Potion earns its slot here more than anywhere else in the game, because nearly everything you are fighting is cold-typed.
• Spawn consumables do nothing. A Water Candle or Battle Potion is a wasted slot, and a Peace Candle or Calming Potion will not quiet anything down either.
• Build flat and open near spawn. The bosses fly and shoot, so boxing yourself in costs more in blocked shots than it saves in hits taken.

Summoners can reasonably ignore this event. The Pumpkin Moon covers most of what a summoner wants and is meaningfully easier, and the mobility items from the two events land in the same range. The Frost Moon's case is its ranged and magic weapons. If none of those are on your list, there is no obligation.

Two things end a run by accident. Summoning a pirate invasion over the top of a Frost Moon cancels it outright. Leaving the world and coming back can also end it early, and anything still lying on the ground goes with it, so finish the night before you take a break.