The Boss Rush can only be retried by picking up an item off a pedestal in its room.If the Boss Rush entrance has closed, the room can still be re-entered by dying in the Mom boss fight room at the cost of another life. If Isaac dies during the Boss Rush, but is able to respawn, the entrance to the Boss Rush room will still be open if the timer is still under 20 minutes.If Isaac is teleported to the Devil Room while inside the Boss Rush room (for example, using a Joker card), exiting the Devil Room will lead him to Mom's Boss Room.If Mom is beaten within 20 minutes and Isaac enters the Devil Room, he must return to the boss room before 20 minutes have passed otherwise, the Boss Rush entrance will be closed.Note that all of the chapter 4 bosses (except Blastocyst and Death) are not present in the Boss Rush:įurthermore, some other bosses are not present in the Boss Rush: Each boss can only appear once per Boss Rush, meaning that out of all the 50 bosses Isaac will face 30 of them. Wave 15: The Fallen and The Headless HorsemanĪll 15 waves are randomized, with each wave spawning two random bosses from the list.Occasionally, all the bosses fought in the Boss Rush will be their Champion variants, if they have one. The next wave does not spawn until both bosses from the previous wave have been killed, and any lingering monsters from previous waves will not prevent the next wave from spawning. The Boss Rush consists of 15 waves with 2 bosses per wave.

20 minute timer with music