Upon use, destroys all obstacles in the current room and deals 200 damage to every enemy (including bosses). This effect also applies to every room for the remainder of the floor.
Leaving the Boss Rush room or ??? entrance room will also close the doors.
Does not open the Boss Rush door from the inside.
Does not open a path to ??? if used in the room on the other side of the flesh door in Mausoleum / Gehenna II.
Entering a room with an angel statue while the effect is active automatically initiates a fight with an Angel.
Does not kill enemies that are immune to damage while entering the room, such as Lil' Haunts.
If used before the Ultra Greed fight begins, it will deal no damage to Ultra Greed, as he is invulnerable for the first few seconds upon first entering his room. However, it will still break obstacles as usual.
When used in Greed mode, it will only activate once for the main room (as opposed to once per wave, in a similar fashion to a standard run). Therefore, its damage potential is maximized if used after all the monster waves have spawned for the current floor.
Mama Mega! + Safety Scissors: Allows for infinite uses of Mama Mega! after finding a Golden Bomb or ? Card, as the extinguished Golden Troll Bombs will turn into Golden Bombs.
Bag of Crafting: The infinite golden bombs created can be used to easily craft high quality items.
Broken Padlock: Mama Mega!'s blast will also open locks.
Golden Bomb: While holding a golden bomb, Mama Mega! can be used once on that floor without consuming it, but will remove the golden bomb from Isaac's consumables (using it a second time consumes it as normal). It may be used again for free on another floor if yet another golden bomb is collected, and so on. Mama Mega! also receives a unique golden sprite in the HUD.
The visual effect has been changed from a simple screen flash and shake to a massive shockwave on entering each room.
Mama Mega!'s effect is one of the only two ways a Bomb Bum can be destroyed.
Mama Mega! may be a reference to the GBU-43, known colliqually as the mother of all bombs due to its massive payload.
Bugs
Bug!
Mama Mega! can break the door to the Knife Piece 2 room. If Isaac leaves this room before the intro animation of Mother's Shadow finishes and then enters it again, another Mother's Shadow will be generated.
Bug!
XboxOnePS4 Mama Mega! cannot be used to open the doors to Boss Rush / ???.