Clattering Skeletons

Dungeon cards are not part of a player's deck or sideboard. In both constructed and limited formats, players can use any dungeon card when they venture into the dungeon.

You can only move forward (well, downward) in a dungeon, never backwards or sideways.

To venture into the dungeon, a player moves their venture marker into the next room of the dungeon they are currently in. If they aren't currently in a dungeon, that player instead chooses a dungeon card from outside the game, puts it into the command zone, and moves their venture marker onto the first room.