

Zodiac collectibles from the base game are placed in Planetarium item pools: Increases tears and speed, but decreases range. Significantly shrinks Isaac, allowing him to squeeze between objects and making some enemy shots pass over him. Frozen enemies slide away and explode into ice shards when touched. Isaac shoots ice tears, which freeze enemies they kill. It begins with 7 orbiting tears when entering a new room.

Isaac is surrounded by an aura which has a chance to absorb incoming enemy tears. There's a short cooldown before Isaac can dash again. Isaac's tears become rocks that have increased knockback and deal variable damage, and have a high chance to destroy obstacles.Ĭharge in a direction by double-tapping the movement key, becoming invulnerable and damaging enemies. Enemies near Isaac are Charmed, causing them to attack other enemies. Upon defeating a boss, activates XIX - The Sun, fully recharges Isaac's active item, and grants bonus damage and luck for the rest of the floor.Īdds one extra Secret Room and one Super Secret Room on each floor.ĭoors stay open after entering a room, even with enemies in it, allowing Isaac to leave any time. If Isaac has Rosary Bead there is a chance for planetarium item to transform into The Bible. If a Planetarium spawns on one of the alternative floors where Treasure Rooms would normally have 2 items to choose from, the Planetarium may still only have one item with no other choice available. They may also contain Signs of the Zodiac. Planetariums are similar to Treasure Rooms, but only contain special astronomy-themed items that are only available through Planetariums. These rooms also have an individual chance to spawn in the purple-tinted areas of the Mausoleum, without Isaac previously skipping any Treasure Rooms. If Isaac enters a Planetarium, the chance will be set to 0% and can't be increased again This chance is further increased by an unknown percentage if Isaac has Magic 8 Ball or Crystal Ball. The Treasure Room must not be entered at all to be considered skipped. The chance for a Planetarium to appear starts at 1% and will increase by +20% whenever a Treasure Room is skipped. These items include the Signs of the Zodiac, Tiny Planet, Magic 8 Ball, and Crystal Ball.

Planetariums are unlocked by possessing three astrology-related items simultaneously. Like Treasure Rooms, they require a key to enter.

The Planetarium is a new unlock-able room type introduced in Antibirth that has a small chance to appear after certain criteria are met. For a list of other rooms featured in Antibirth, check out Chapters.
