The Beast

*The Beast* is a boss added in *The Binding of Isaac: Repentance* DLC. She appears in Home and is the final boss of Ending 22, as well as *The Binding of Isaac* as a whole.

## Behavior

After defeating Dogma, Isaac is given , granting him flight and allowing him to traverse The Beast's 2D Crawl Space-like arena.  also grants a one-time  shield, the effect of  (if playing in Normal Mode), Prevents Isaac's speed from going under 1.1, and +2 damage, and heals him up to 6 hearts with Red Heart Containers and Soul Hearts.

At the start of the fight, The Beast sits inactive in the background. Flying around The Beast are four Ultra Harbingers, which attack Isaac one at a time in the order of Ultra Famine, Ultra Pestilence, Ultra War, and Ultra Death. Once they have all been defeated, The Beast lets out a roar, submerges into the lava, then reemerges on the right side of the screen, beginning her fight.

### Phase 1

During her first phase, The Beast uses the same sequence of attacks indefinitely:

* Charges towards Isaac, forcing the screen to scroll while harmful, destructible stalagmites and stalactites move towards Isaac.
	+ The screen scrolls along with The Beast, meaning that she will not get closer to Isaac even if he doesn't move; this attack only brings the stalagmites and stalactites on-screen.
* At the end of the charge, The Beast begins to inhale large rings of fire which have one small gap that Isaac can fit through.
	+ Any remaining stalagmites or stalactites on-screen are destroyed at the start of this attack.
* After inhaling 8 rings of fire, The Beast stops and fires a colossal -like beam that covers the bottom and middle portions of the screen.
* After this attack, she performs a quick charge across the screen before repeating the initial charge in the opposite direction. Similar to the -like beam directly before, she covers a large portion of the bottom and middle parts of the screen.

Even if The Beast's HP drops below the threshold for her second phase, this will always still be the first attack she performs every single time.

### Phase 2

The Beast enters her second phase below 6660 HP and loses her inhaling attack, but gains 2 new ones. Additionally, during the charging attack, there are more rocky obstacles and some stalactites are cracked and fall when Isaac passes underneath. (As before, the screen scrolls while The Beast charges, with Isaac's position on the screen being maintained.)

At the end of a charge, The Beast performs one of two attacks:

* Opens her mouth and fires 3 radial waves of slow-moving fire, then fires 6 radial strings of fast-moving projectiles which travel through the gaps left between each fire.
* Roars and spawns 4 Beast Souls which chase Isaac and charge at him, trying to predict his movements, before dissipating.
	+ Any remaining stalagmites or stalactites on-screen are destroyed at the start of this attack.

After using either of these attacks, The Beast submerges into the lava and causes glowing orange lines to appear beneath Isaac and in other random areas. The glow of these lines increases in intensity over time before launching out a large fiery projectile that flies up and falls back into the lava. The Beast gradually increases the rate at which projectiles are launched before eventually reemerging from the lava on the opposite end of the screen and launching a small burst of large fiery projectiles arcing in all directions.

* Any remaining stalagmites or stalactites on-screen are destroyed at the start of this attack.

### Phase 3

The Beast enters her third phase at approximately 33% HP and is indicated by a burst of blood. The Beast is forced to submerge into the lava and reappear on the other side of the screen, then begins charging towards Isaac indefinitely while more stalagmites and stalactites spawn behind him. (As before, the screen scrolls while The Beast charges, with Isaac's position on the screen being maintained.) Cracked stalactites do not appear during this phase.

Once The Beast's HP reaches approximately 2000, her horns crack and her body ruptures in boils. She degrades through two more stages: losing 2 horns and an eye upon reaching roughly 1000 HP, and losing another eye, another horn, all of her teeth, and generally having a melted look upon reaching roughly 500 HP. Upon defeat, a large light ray comes from above and strikes her down, followed immediately by Ending 22.

## Gallery

* The Beast in-game.
* The Beast charging.
* The Beast slightly damaged.
* The Beast very damaged.
* The Beast extremely damaged.

## Unlockable Achievements

* Options? - Defeat **The Beast** as  Isaac.

* Candy Heart - Defeat **The Beast** as  Magdalene.

* A Pound of Flesh - Defeat **The Beast** as  Cain.

* Redemption - Defeat **The Beast** as  Judas.

* Montezuma's Revenge - Defeat **The Beast** as  ???.

* Cracked Orb - Defeat **The Beast** as  Eve.

* Empty Heart - Defeat **The Beast** as  Samson.

* Lil Abaddon - Defeat **The Beast** as  Azazel.

* Astral Projection - Defeat **The Beast** as  Lazarus.

* Everything Jar - Defeat **The Beast** as  Eden.

* Hungry Soul - Defeat **The Beast** as  The Lost.

* C Section - Defeat **The Beast** as  Lilith.

* Keeper's Box - Defeat **The Beast** as  Keeper.

* Worm Friend - Defeat **The Beast** as  Apollyon.

* Spirit Shackles - Defeat **The Beast** as  The Forgotten.

* Jar of Wisps - Defeat **The Beast** as  Bethany.

* Friend Finder - Defeat **The Beast** as  Jacob and Esau.

* Glitched Crown - Defeat **The Beast** as  Tainted Isaac.

* Belly Jelly - Defeat **The Beast** as  Tainted Magdalene.

* Blue Key - Defeat **The Beast** as  Tainted Cain.

* Sanguine Bond - Defeat **The Beast** as  Tainted Judas.

* The Swarm - Defeat **The Beast** as  Tainted ???.

* Heartbreak - Defeat **The Beast** as  Tainted Eve.

* Larynx - Defeat **The Beast** as  Tainted Samson.

* Azazel's Rage - Defeat **The Beast** as  Tainted Azazel.

* Salvation - Defeat **The Beast** as  Tainted Lazarus.

* TMTRAINER - Defeat **The Beast** as  Tainted Eden.

* Sacred Orb - Defeat **The Beast** as  Tainted Lost.

* Twisted Pair - Defeat **The Beast** as  Tainted Lilith.

* Strawman - Defeat **The Beast** as  Tainted Keeper.

* Echo Chamber - Defeat **The Beast** as  Tainted Apollyon.

* Isaac's Tomb - Defeat **The Beast** as  Tainted Forgotten.

* Vengeful Spirit - Defeat **The Beast** as  Tainted Bethany.

* Esau Jr. - Defeat **The Beast** as  Tainted Jacob.

## Damage Scaling

Damage scaling is an unclear mechanic introduced by Nicalis in The Binding of Isaac: Afterbirth to provide a more challenging experience to the players, enabling *some* enemies to retaliate against high-damage attacks by deploying an "armor" of a sort to greatly reduce the amount of damage taken. Further details and an in-depth explanation may be found here.

## Notes

* Phase 2's narrow activation period (from 50% to 33% health) means it will often be skipped, typically if enough damage is done during the long-duration fire rings attack.
* makes it nearly impossible to avoid damage when The Beast inhales lines of fire because it changes the speed of just the fires within its area of effect. Instead of having a consistent gap in each line of fire, the gap may be filled in by other lines of fire moving at inconsistent speeds.
* doesn't work on The Beast.
* , "I'm Drowsy..." pill, etc. works for the duration of the fight, and makes for an easy battle.
* will float in the air for the duration of the flight and remains in place during the chase sequence, providing constant extra damage.
* works and will kill The Beast before dying, triggering Ending 22. It must be used after all four Ultra Harbingers are defeated, or else it will only kill the current Ultra Harbinger.
	+ However, if the "I'm Drowsy..." pill was used in the boss room, using  would kill Isaac right before the Beast's death animation's end.
* All teleportation items/cards cannot be used to escape the fight; instead, Isaac will be teleported to a random spot on the screen. Similarly, any respawn items will respawn Isaac immediately, without restarting the fight. Essentially, there is no way to leave the fight after it has begun, outside of  and .
	+ is capable of creating a portal in the fight if it consumes enough pickups. Going into the portal will return Isaac to an unexplored room in Home and softlock the run as it is not possible to return to the boss fight.
* and  travel in an arc, similar to Ultra Pestilence's shots, and are extremely hard to aim. If Isaac has high range when firing left or right, the projectiles will go up and off-screen.
* Most non-flying familiars, such as , , or Blue Spiders, are almost completely useless against the Ultra Harbingers, as the familiars will stay stuck in the lava on the bottom of the arena. However, they can damage Ultra War if his movement pattern takes him close enough to the bottom of the screen, and The Beast as she is half-submerged in lava.
* Any item that gives an effect for the room, such as  or , will work for the entire fight, starting with Ultra Famine.
* can affect this fight. However, it only activates for 1 unvisited room out of 4. Finishing the fight with Dogma and beginning the fight against the Ultra Harbingers counts as a new visited room. Hence, to have the effect against The Beast, the last visited room in Home must be the 3rd after the effect was triggered for the last time.
* works as normal in this fight — as long as Isaac stays still and has some way of dealing damage without moving or firing, such as an enemy-chasing familiar. He will eventually kill The Beast with enough patience.
* Homing  will stay on-screen indefinitely during this fight.
* makes tears travel straight down, as there is no ground they can skip on.
* Like , bombs fired with  will be fired in a downward arch since there's no ground for them to slide on, making it a difficult item to use in the fight without bomb immunity items such as  or .
* Defeating each Ultra Harbinger will grant Isaac's active item 2 charges, similar to the Boss Rush.
* All items that grant extra lives will revive Isaac on the spot rather than returning him to the previous room.
	+ Accordingly,  is incredibly useful in the fight, due to the large number of lives it provides Isaac.
* The Soul is capable of dragging  The Forgotten with him as he moves. This means he can move anywhere on the screen, but at a much slower rate.  Tainted Forgotten flies during this battle and stays where he ends up when thrown (in mid-air), meaning that if you throw him at the Beast you can constantly attack its during the chase scenes.
* The hitboxes of stalactites, stalagmites, and the lava persist during The Beast's death animation.
* The stalactites and the stalagmites, while acting like obstacles, actually count as enemies, allowing abilities that proc on enemy death or damage, like the , to work with them. This trinket in particular makes the chase portions a breeze, as The Beast destroys the stalactites and stalagmites automatically.
* Despite not being able to fly or go over gaps in its final form,  will be able to "fly" around the arena and deal damage without sinking in the lava. Bombs placed by Bumbo still behave normally and fall.
* Tears that go up and off-screen, such as those created by  explosions, are affected by "gravity" in this fight and fall back down at an enemy. It's unknown if this is a bug or a feature.
* is very difficult to use. The unique tear seems to be teleported back to the player sometimes, maybe because it gets "lost". Because of the screen scrolling, it may be dragged out of the screen if the player doesn't make it move with the scrolling. Keeping the tear in sight, making it move, moving the character to avoid obstacles such as stalactites, and taking care of The Beast all at the same time is a mess unless having a synergy that makes the tear more visible and/or very powerful. With powerful synergies,  can make this fight very easy. However, without it, it makes it harder.
	+ On PC, all of these issues can be negated by enabling mouse controls. The cursor moves with the screen, meaning the left mouse button can simply be held in place and the tear will successfully follow its target.
* Bombs are affected by gravity and are hard to hit the Ultra Harbingers with, but can easily be used against The Beast, especially during chase sequences. As such, it is a great strategy to continuously use all of your bombs during this sequence, as there is no longer any other need for them.
* Because there are no walls or floors for tears to collide with in this fight, the damage boost from  will not fade away.
* Items that place Poops, such as  or , cannot place poops during the fight.
* The lava projectiles from both the lava and when The Beast rises afterward can be slowed and knocked down with certain slowing items such as  and high knockback tears.
* is not recommended for this boss battle, as it can cause flames to pile up unavoidably during the Beast's fire ring inhalation attack.

## Trivia

* The Beast is heavily based on the first Beast described in the Book of Revelation.
	+ The Beast's theme is called "Revelations 13-1", referencing the section in the Book of Revelation describing the first Beast.
		- A narration performed by Matthias Bossi reads the second verse of this passage during the cutscene before The Beast's fight. This narration says, "And the beast which I saw was like unto a leopard, and his feet were as the feet of a bear, and his mouth as the mouth of a lion: and the dragon gave him his power, and his seat, and great authority."
* The Beast appears to be wearing a tattered version of Mom's dress, suggesting that it is yet another interpretation of Mom from Isaac's perspective.
* The Beast is the only boss to be preceded by an introductory cutscene rather than a VS screen.
	+ The cutscene depicts Isaac being crushed by a giant static cross that rises from the remains of Dogma, which turns his tears into static. Following this, the room begins collapsing, revealing a hellish cavern while Isaac sprouts a pair of wings and flickers between resembling  ???,  The Forgotten, and  The Lost. Isaac then flies up to face The Beast rising from the lava.
		- Isaac's flickering between ???, the Forgotten, and the Lost is a reference to the events of Ending 20.
		- Additionally, there being 3 characters total in the cutscene (which conveniently) shows up right after Dogma ; as well as **Beast** having three eyes and horns could be hinting at  and "Holy Trinity" concept, showing how Mom's poor understanding of the material affected her persona in a bad way.
* The Beast is one of the only 2 bosses to take place in a Crawlspace-like side-scrolling environment, the other being Rotgut.
* At the end of the fight, Isaac's father refers to The Beast as "the Mother of Harlots."
* When using the "I'm Drowsy..." pill during the battle with the Ultra Harbingers, there is one extra slow sign in the position of where The Beast will be, indicating that The Beast is actually "hidden" below the lava before the Ultra Harbingers are defeated.
* Revelations 13-1 is the longest track in the entire *Rebirth* OST, sitting at 7 minutes and 53 seconds. This makes sense, as the theme is highly dynamic, changing depending on where the player is in the fight.
	+ During the section that plays while fighting The Beast, Latin chanting can be heard in the background sometimes. The chanting is "mori bestia, cum nostra lucis", which is a mistranslation of "die, Beast, to our light". A more accurate translation would be "Morere, bestia, ab luce nostra".
* In Revelation, it is said that the Lord is the one who defeats The Beast, which may explain the beam of light that comes down to kill The Beast.
	+ If The Beast is affected with any Status effects as she dies, the beam of light changes color. This is likely because the beam of light is part of The Beast's frames and not a different entity entirely.
* Enemies turned into poop with  or other means affect the game's scrolling, as the poop will remain on the screen regardless of whether or not the screen is scrolling.
* In the fight's background, each of the four Harbingers can be seen doing a small animation before they fly into the foreground. Ultra Famine chuckles, Ultra Pestilence raises his fists in the air, Ultra War becomes enraged, and Ultra Death facepalms before brandishing his scythe.
	+ They can also be seen doing a small animation whenever Isaac takes a hit. Ultra Pestilence waves his arms and grins, Ultra War raises his arms and then "slams" them down, and Ultra Death laughs. Ultra Famine doesn't have one because he is the first Ultra Harbinger to come into battle.
* According to the game files, The Beast's boss fight takes place in Hell itself.
	+ Despite being in a standard fire-and-brimstone depiction of Hell, Isaac's last will still retains Home's "some cold place" location line, suggesting some level of illusion to the events of The Beast.
	+ Edmund McMillen has referred to the place as the Lake of Fire on Twitter.
* The Beast is confirmed to be female.
* The four Beast Souls that The Beast spawns may be a reference to *The Binding of Isaac: Four Souls*, a card game created by Edmund McMillen.
* The Beast was teased initially in a post made to Steam by Edmund 5 days before Repentance's release, which included an artwork that featured its faint silhouette in the background.
* The skull of The Beast can be seen in the icon for the  Dead God achievement.
* The earlier concept art depicts The Beast to have extra four heads based on the Harbingers.
* Edmund McMillen noted that the Beast sequence, along with the Tainted Characters and Dogma, was initially reserved for a possible Isaac sequel.

## References

1. ↑ https://twitter.com/edmundmcmillen/status/1408676530201366528
2. ↑ https://twitter.com/edmundmcmillen/status/1410142261615075330
3. ↑ https://twitter.com/edmundmcmillen/status/1442955314312056834
4. ↑ https://twitter.com/edmundmcmillen/status/1487577680044195840