Sacrificial Altar

**Sacrificial Altar** is an unlockable activated item added in *The Binding of Isaac: Afterbirth † (Booster Pack #5)*.

## Effects

* Upon use, sacrifices up to 2 familiars and spawns an item for each familiar sacrificed.
	+ The order in which the familiars were obtained does not matter; it picks 2 at random to sacrifice.
	+ If Isaac has no familiars, no Blue Flies, no Blue Spiders and no Clots, the item will do nothing and will not be consumed.
		- Even if Isaac doesn't have any familiars, if he has a single fly, spider, or locust, the item will be consumed.

* The list of possible rewards include:

* +

* If Isaac already has all of the above items, one or two copies of  are spawned.
* In addition to the familiars, any Blue Flies, Blue Spiders, Locusts, or Clots will be converted to 1 Penny each.
* On use, causes a brief Curse of Darkness effect for a few seconds.

## Notes

* If playing as  Lilith, the  familiar cannot be sacrificed.
* Charmed and friendly enemies cannot be sacrificed.
* Any Pretty Flies are counted as a single sacrifice.
* Familiars spawned from Trinkets like  can be sacrificed, destroying the trinket in the process.
* Upon use may remove Transformations.

## Synergies

* +  as  Judas /  Dark Judas: Grants +10.8 temporary damage up for every sacrificed familiar. The damage bonus scales down to 0 over time, similarly to . Sacrificing blue flies or blue spiders has no special effect.
* : Converts each wisp into a Half Red Heart. Spawns a single red and black wisp in the middle ring after the sacrifice.
* : Spawned fly turrets count as familiars for sacrificing; although dropping the Brown Nugget will despawn the last fly turret, older ones will remain and can be sacrificed.
	+ Spawned fly turrets count as regular blue flies for sacrificing, and thus are converted to pennies.
* /  / : 2 Black Hearts will also drop.
* : Can remove the Isaac's Heart familiar while the item remains, making Isaac invulnerable.
* : Summoned familiars can be sacrificed since they persist for the entire floor, even without holding the item.
* : Using Plum Flute, then using Sacrificial Altar will remove the Baby Plum spawned and spawn an item. The Plum Flute is not removed upon doing this, and subsequent usage of Plum Flute still summons Baby Plum normally.
* : When absorbed by Void, the one time use no longer applies, unlike other one time use active items. Familiars can be sacrificed with every activation of Void.

## Interactions

* : Cannot be sacrificed in itself, but Locusts can be sacrificed for one coin each, much like Blue Flies.
* : Locusts created from Abyss are counted as familiars and can be sacrificed as normal.
* /  : The altar consumes the whole familiar, up to 4 cubes or balls at a time. If more than 4 are available, they count as other familiar(s) that may be separately chosen for sacrifice.
* /  /  / : These familiars can be sacrificed only when they're active.
* /  /  / : The familiars generated by these items can be sacrificed and turned into items.
* : No effect; only spawns one item per familiar sacrificed, and can only sacrifice up to 2 familiars.
* : The Altar ignores the effects of Chaos, always spawning items from its usual drop pool instead of a random pool.
* : The transformation will be lost if Isaac has less than three items needed after using Sacrificial Altar.
* : Each Dip spawned by Dirty Mind is turned into a coin, regardless of type.
* : Converts all micro-Isaacs into one coin each upon use.
* : Both flies created by this item are counted as a single sacrifice each, due to the fact that they are counted as pretty flies.
* : The Intruder can be sacrificed even while it's in Isaac's head.
* : Created familiars can be sacrificed. Additionally, converts each wisp into a Half Soul Heart. The passive item effects granted by the familiars is retained for the duration of the floor.
* : Lil Delirium may be sacrificed, but the item is not removed. The familiar will return once another familiar is gained or lost, or the run is quit and resumed.
* : Body familiars that are spawned by this item can be sacrificed by switching between the Pinking Shears and Sacrificial Altar.  However, the body familiars reappear when picking one of the spawned items up.
* : Pretty Flies can be sacrificed, but quickly regained due to The Swarm spawning more flies.
* : The item will be lost, and each spawned familiar counts as one sacrifice. If Quints is sacrificed first (or is the only item available to sacrifice) and at least two familiars are summoned, two Devil Room items will be spawned while only losing one item.
* : Although not readily apparent as a familiar, the Star can be sacrificed. It will be destroyed even if it is not currently in the same room.
* : Each Clot spawned by Sumptorium is turned into a coin, regardless of type.
* : Super Bum may be sacrificed, but none of the items will be removed. The familiar will return once another familiar is gained or lost, or the run is quit and resumed.
	+ Super Bum may be sacrificed but only one of the items will be removed.
* : A Gemini familiar granted by Zodiac can be sacrificed without losing the item.

## No effect

The following familiars, followers, and orbitals *cannot* be sacrificed:

## Trivia

* Sacrificial Altar is based on this Steam Workshop item by Niro and PJJLegend, originally known as Satanic Ritual.

## Gallery

* Sacrificial Altar's appearance in the original Steam Workshop mod.