The door to the Mausoleum / Gehenna will appear after defeating the boss in Mines II / Ashpit II or Depths I / Necropolis I / Dank Depths I. The door will *not* spawn after defeating Mom. It costs two full hearts to enter, and ignores almost every form of damage reduction, including The Wafer and invincibility. Unlike other methods of health donation, red hearts will not be prioritized over more valuable hearts.
- The Lost, Tainted Lost, Tainted Jacob (In his soul form), Tainted Soul (unless he is holding Tainted Forgotten), and any character under the effect of Soul of the Lost can enter the door for free.
- Dad's Key, Get out of Jail Free Card, Mr. ME!, and Sharp Key can be used to open the door without taking damage.
- Broken Padlock can be used to open the door with one bomb.
- Cracked Orb's effect can open the door with less damage taken than needed, or with no damage with Dull Razor.
- The extra characters spawned by Strawman, Soul of the Forgotten, and Soul of Jacob and Esau can expend their health to open the door.
- Crow Heart can be used to open the door with red hearts first.
The boss of Mausoleum II is always a more powerful version of Mom. After Mom is defeated, a trapdoor that leads to Womb II, and a sealed fleshy door both appear. Stabbing the door with the knife familiar created by Knife Piece 1 and Knife Piece 2 will cause it to open, leading to a more difficult version of Mom's Heart. Defeating Mom's Heart will cause the boss room to darken, and the trapdoor to Womb II will now lead to the Corpse.
- A Sharp Key can be used in place of the Knife.
- Cracked Orb's effect can open the flesh door, allowing Isaac to keep the knife.
- If Isaac exits the Boss Rush room after 25 minutes have passed, there is a chance that the flesh door will change positions to the wall where the boss rush door was, causing Isaac to "come out" of the flesh door and leaving it open, allowing entry without the knife.
- After this special version of Mom's Heart is defeated, any Item or Pickup that was left behind anywhere on the floor will disappear (including Shop items etc.): the floor will be empty.
The alternative floor to Mausoleum is Gehenna. It is unlocked after all bosses from this floor have been defeated.
||883.0||Floats toward Isaac, avoiding his shots. After getting close, fires a short Brimstone laser in the closest cardinal direction and propels itself away from him.|
||251.0||Starts attached to the wall or an obstacle. After a while, it detaches, firing 6 blood shots in all directions, turning the room dark, becoming invisible and chasing Isaac. Briefly becomes visible upon getting hit.|
||885.0||Creates an indestructible, homing Purple Ball at the start of the room and follows it around, occasionally leaving it to revive enemies that have died in the current room.|
||885.1||Wanders around the room and fires a line of blood shots and creep if Isaac is on either side of it. Can summons bone traps that temporarily ensnare Isaac if he walks into them.|
||227.0||Wanders around the room and throws a bone at Isaac when he is in sight.|
||841.0||Slowly wanders around the room, stopping to fire a large line of fire at the player.|
||841.1||Wanders around the room slowly, stopping to fire lines of flames in the cardinal or ordinal directions, rotating in an attempt to hit Isaac.|
||404.1||Floats towards Isaac, doing contact damage.|
||212.0||Invulnerable enemy that moves diagonally around the room, dealing contact damage. Dies when the room is cleared.|
|Cursed Death's Head
||212.2||Invulnerable enemy that moves diagonally around the room, dealing contact damage. If Isaac enters its purple aura, he will be inflicted with fear and be temporarily unable to shoot. Dies when the room is cleared.|
||886.0||Spawns with a Fetal Demon attached to it and slowly walks towards Isaac. Will occasionally fart, briefly pushing the demon away and spawning creep around itself and the demon. If the demon is killed first, the Fatty will shoot out Brimstone in the diagonal direction closest to Isaac. It will then fly around the room diagonally, bumping off of walls and tall blocks all while continuously firing Brimstone behind it.|
||886.1||Usually encountered tethered to Vis Fatties. When tethered it makes short lunges towards Isaac if he gets close. If the Vis Fatty is killed or when encountered alone it will chase Isaac similarly to Gemini's Suture.|
||13.0||Hovers in place. Does not deal contact damage and is harmless but can turn into Pooters if they stay around Poop.|
||96.0||Invulnerable fly that circles Corny Poop and various monsters. Deals contact damage. Turns into a vulnerable Attack Fly after the object or monster it circles is destroyed.|
||61.0||Flies slowly towards Isaac, exploding into 4 shots in the cardinal directions upon death.|
||61.3||Flies slowly towards Isaac. Spawns a vortex that fires four Brimstone beams in the cardinal directions upon death.|
||834.0||Runs around the room, sprinting at Isaac when he gets in its line of sight and lashing at him when it gets close.|
||834.1||Runs around the room, sprinting at Isaac when he gets in its line of sight and throwing out its whip when he gets in range.|
||834.2||Runs around the room. When Isaac gets in its line of sight, continuously chases him and lashes its whip, occasionally deflecting Isaac’s shots.|
||24.3||Chases Isaac, dealing a full heart of contact damage. Upon taking enough damage, it collapses into 1-2 piles of goo, each of which can be killed and regenerate after a short period of time if not killed quickly. These goo piles have less health the more times the Cursed Globin splits.|
||41.2||Moves erratically around the room, charges toward Isaac when in line of sight. When its health is depleted, it turns into a Brainless Knight and a Pon.|
||41.3||Alternates between running around the room along the cardinal directions and aimlessly walking in circles. Charges at Isaac when in line of sight. Dies when its corresponding Pon dies.|
||840.0||Hops around the room, leaving damaging red creep wherever it lands. Upon death, its associated Brainless Knight dies with it.|
||248.0||Stationary enemy that fires a homing shot at Isaac when he gets in range of them.|
||26.2||Slowly floats towards Isaac, firing homing shots at him when he is in their range. Spawns with an Eternal Fly orbiting around it.|
|Rag Man's Ragling
||246.1||Quickly leaps towards Isaac and deals contact damage. Randomly shoots two purple shots that orbit around it.|
||892.0||Slowly floats toward Isaac, swells up and fire 6 blood shots in all direction upon taking damage. Explodes upon death, healing nearby enemies and leaving a big puddle of red creep.|
||836.0||Randomly wanders around the room. Pauses to charge and fire a homing Brimstone laser when Isaac gets in its line of sight.|
||260.0||Floats toward Isaac and occasionally fires a blood shot at him, predicting his movements.|
||833.0||Flies around the room and propels itself by spawning flames.|
||816.1||Uses telekinesis to pick up and throw rocks and obstacles at Isaac.|
||805.0||Shields all enemies in the room, preventing them from taking damage. Fires shots in the cardinal directions when it takes damage.|
||306.1||Spawns fly and spider enemies until it is destroyed.|
||44.0||Slides around the room aimlessly, damaging Isaac by contact. Disappears when the room is cleared.|
||44.1||Quickly slides towards Isaac when he gets in its line of sight, then moves slowly back to its original position. Cannot be destroyed.|
||218.0||Moves around the room like Guts, damaging Isaac by contact. Cannot be destroyed.|
||877.0||Quickly slides towards Isaac when he gets in its line of sight. Cannot be destroyed.|
||42.0||Stationary and invulnerable monster that occasionally fires a blood shot at Isaac. Stops firing when room is cleared.|
||42.2||Stationary and invulnerable monster that occasionally fires a triple shot at Isaac. Stops firing when room is cleared.|
|Constant Stone Shooter
||202.0||Stationary and invulnerable monster that continuously fires shots in a single direction.|
||235.0||Stationary and invulnerable monster that sucks Isaac towards it, along with Isaac's tears and enemy projectiles.|
|Broken Gaping Maw
||236.0||Stationary and invulnerable monster that sucks Isaac towards it, along with Isaac's tears and enemy projectiles. Alternates between active and inactive every couple of seconds. Has a stronger attraction power than a regular Gaping Maw.|
|The Heretic||The Siren||Mom||Mom's Heart|
- In Antibirth, fully constructing The Knife required 3 Knife Pieces, with the third appearing in Mausoleum II. For Repentance, however, the third piece was removed, and the completed knife only requires the player to obtain two pieces from Downpour and Mines.
- Also in Antibirth, there was a mechanic where somewhere on the floor, there was a special Teleporter that usually required solving a puzzle, having flight, or using pickups to access. This Teleporter led to a second section of the floor, a cluster of rooms with enemies and a few random special rooms. Since this second area was on the same map as the main part of the floor, it could also be accessed by using the Red Key enough times to reach it, or by teleporting to it with other means. Both floors of the Mausoleum had this feature, and in Mausoleum II it was required to go there to solve a puzzle in order to unlock Knife Piece 3. However, like Knife Piece 3, this mechanic was also removed in Repentance.
- The Visage was originally a Mausoleum boss in Antibirth, but it was changed in Repentance to appear on Mausoleum's alternate floor, Gehenna. Its appearance was also updated from purple to red to reflect this.
- This might have been because of Gehenna's "torture chamber" theming, which Visage complements more so than Mausoleum's occult theming.
- Mausoleum is referred to on Isaac's Last Will as "Some Cursed Place".
|Chapter 1||Chapter 2||Chapter 3||Chapter 4||Optional||Chapter 5||Chapter 6||Endgame|
|The Binding of Isaac: Rebirth|
|Achievements||Attributes||Bosses||Cards and Runes||Challenges||Chapters|