Binding of Isaac Achievement: Dull Razor
In-Game Secret Number
Alt stage to the womb.
Defeat It Lives 30 times
Get a 3-win streak
Collect 10 "tears up" items or pills in one run
Defeat Ultra Greedier as The Lost
Complete a floor after Basement I, start-to-finish, with only half a heart of health (can use The Lost)
Complete challenge #35
Defeat The Lamb without taking hearts, coins, and bombs through an entire run
Have The Battery, 9 Volt, and Car Battery in your collection
Complete 2 Victory Laps and start a 3rd
Alt stage to the caves.
Defeat It Lives 16 times
Defeat Ultra Greedier as Azazel
Open 20 locked chests
Collect every item in the game, unlock all secrets and endings, and complete the Bestiary
Unlocked a new challenge.
Defeat Mom for the 1st time
Unlocked new enemies!
Defeat The Lamb for the 1st time
Alt stage to the basement.
Defeat Mom's Heart 11 times
Unlocked a new co-player baby.
Earn all Hard Mode Completion Marks as Apollyon
Beat Chapter 4 without taking damage