Arcturus is a passive item in Glacier's Laboratory, a mod for The Binding of Isaac.

Entering uncleared rooms often spawns a unique Mulligan enemy marked with a crown mark.

The Mulligan is not required to clear the room, however it has extra health equal to 75% of all enemies' total health in the room. If there are no enemies other than itself, it instead has its health multiplied by 1 + 0.5 * CurrentStage.

Killing the Mulligan in time will instantly clear the room and destroy all enemies and projectiles.

Gives Isaac a shotgun that can fire up to 2 shots by pressing and holding fire button, each pellet deals 75% Isaac's damage. Once used, the shotgun must be reloaded by releasing fire button.

If the shotgun is used against the crown mark Mulligan, each pellet also deals extra damage equal to 6.25% of the Mulligan's max health.

Arcturus can be found in the following item pools:

The following tags are applied to this item:

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