These rooms need one coin to be opened. An Arcade can only spawn on an even floor (Basement II, Caves II, Depths II, Utero II), or an XL floor, if you have 5 coins or more when you leave the previous floor.
An Arcade can contain:
- A Slot Machine, a Skull Game, and Blood Donation Machine
- Two Blood Donation Machines, a Beggar, a Devil Beggar, and a Key Master
- A Slot Machine, a Blood Donation Machine, and a Fortune Telling Machine
- A Donation Machine and a Blood Donation Machine
- A Beggar, a Skull Game, a Devil Beggar, and a Blood Donation Machine
- A Slot Machine, a Donation Machine, and Blood Donation Machine
In addition, the Arcade usually also has one or more random Pickups on entry.
Boss Challenge Room
Super Secret Room
I AM ERROR