The Binding of Isaac: Rebirth
79 Achievements
1,520
680-1000h
Boss Rush
Beat the Boss Rush. Details for this achievement will be revealed once unlocked
20
21.75%
How to unlock the Boss Rush achievement in The Binding of Isaac: Rebirth - Definitive Guide
Time for the guide.
To get to Boss Rush, You must defeat mom in under 20 minuets. When you do that a hole in the wall will appear, go inside it. You will see 4 items always random; when you pick one up the boss rush begins. The boss rush has every boss you can fight in the game up-til the mom fight. once you beat the last boss,another Item will drop and you have beaten the Boss Rush Congratulations.
I recommend using azazel as he starts out flying and does the most damage at the start of the game. you also just have to play fast, just find the Item room and fight the boss. It's all luck of the draw on what items you get, you just have to have luck. The best Item to have is the or stopwatch (unlocks after donating 999 coins to shop) as it slows down enemies in every room; Making it easier to clear rooms fast.
The door to Boss Rush only opens if you beat Mom in 20 minutes or less, try to get the treasure room and go straight to the boss on every floor. Use bombs on doors to bypass a room if you think it will take a long time to clear. Once you enter Boss Rush there will be four random Items to choose from. Picking up an item will cause the other three to disappear and start the Boss Rush.
The Boss Rush consists of 15 waves with two bosses per wave. 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. Completing the Boss Rush will also reward one more item.