Start room
What it gives: Nothing. The first room of a floor is always calm.
How it works: You arrive here from the hatch of the floor above. Look at the map before you leave: it shows which doors lead to dead ends.
Rooms
The room types on a floor map and what each one gives.
Reading the map
A floor is a grid of rooms grown from the start room: 9 to 11 rooms on the first floor, two more for every floor deeper.
Special rooms sit only at dead ends. The boss room takes the dead end farthest from the start. Treasure, shop, shrine and sometimes a fountain and a challenge room take the next ones.
Cleared rooms stay cleared. The map shows the rooms you have seen, and the Pilgrim map shows the whole floor.
Combat rooms pick from 32 shared layouts plus two that belong to the floor. Boss rooms use one of 5.
Every trap warns before it hurts: vents glow and smoke, spore pods swell, bone spikes poke their tips out, the sweeping light shows its path first. Traps hurt monsters too, and they go to sleep once the room is cleared. Lava is the exception.
Combat room
What it gives: Sometimes a wooden chest, or one of: coin, half heart, key, bomb.
How it works: Two waves on the first rooms, three later. Each wave lasts 16 seconds, and the doors open when the last monster dies. Luck improves the drop.
Elite room
What it gives: A gold chest and a key from the elite itself.
How it works: One elite monster plus two waves. Elites are tough, resist knockback and have a signature attack. They appear in rooms at least two steps from the start; deeper floors have more of them.
Treasure room
What it gives: One item on a pedestal: a relic, or a body part about a third of the time. Free.
How it works: A dead end with no fight. You take the item by walking into it.
Shop
What it gives: Three goods out of six kinds: heart, key, bomb, relic, weapon, body part.
How it works: A heart costs 3 gold and adds a full heart of maximum health. A key or two bombs cost 5. A relic, weapon or body part costs 15. The Merchant seal takes 15% off.
Shrine
What it gives: A choice of three offers, like a level-up (four with the Fourth candle).
How it works: Costs one heart of current health, once. It will not take your last heart. Worth it when your build lacks one piece.
Fountain
What it gives: Heals you to full, once.
How it works: Do not use it at full health. It stays in the room, so you can come back after a hard fight.
Challenge room
What it gives: A gold chest.
How it works: Four waves instead of two or three, with extra heat so monsters are tougher. Enter at good health.
Secret room
What it gives: Seven coins and a wooden chest.
How it works: Hidden behind a cracked wall next to several rooms. Break the wall with a bomb. The Divining rod shows where it is.
Boss room
What it gives: A gold chest that needs no key, a hatch down, eight coins and thirty souls.
How it works: The dead end farthest from the start. One boss, no waves, and the room has one of five arena layouts. The hatch appears only after the boss falls.