A Devil Room / Angel Room Door will always spawn after every boss fight, excluding the first floor and floors after Utero II/Womb II.
Quote
"He accepts your offering"
Effects
A Devil Room / Angel Room Door will always spawn after every boss fight, excluding the first floor and floors after Utero II/The Womb II/ Scarred Womb II.
The spawned door will not disappear when leaving and re-entering the boss room.
Synergies
Duality - Both Angel and Devil Room doors spawn after every boss, and the selected door will never disappear.