The Lamb

Then I saw a Lamb, looking as if it had been slain, standing at the center of the throne, encircled by the four living creatures and the elders... The Lamb had seven horns and seven eyes, which are the seven spirits of God sent out into all the earth. [...] Then I heard every creature in heaven and on earth and under the earth and on the sea, and all that is in them, saying: “To him who sits on the throne and to the Lamb be praise and honor and glory and power, forever and ever!” [...] I watched as the Lamb opened the sixth seal. There was a great earthquake. The sun turned black like sackcloth made of goat hair, the whole moon turned blood red, and the stars in the sky fell to earth, as figs drop from a fig tree when shaken by a strong wind. The heavens receded like a scroll being rolled up, and every mountain and island was removed from its place. Then the kings of the earth, the princes, the generals, the rich, the mighty, and everyone else, both slave and free, hid in caves and among the rocks of the mountains. They called to the mountains and the rocks, “Fall on us and hide us from the face of him who sits on the throne and from the wrath of the Lamb! For the great day of their wrath has come, and who can withstand it?” —Revelation 5:6, 5:13, and 6:12-17 The Lamb is the boss of the Dark Room, and the final boss of Ending 15. • Backasswards - Defeat ??? or The Lamb Defeat Mega Satan and unlock The Negative. • Ultra Hard - Defeat ??? or The Lamb. Possession of The Polaroid / The Negative is required, barring getting to Dark Room through a Sacrifice Room. Defeat Mega Satan and unlock The Negative. • The gate is open! - Defeat The Lamb. • Golden God! - Defeat ??? and The Lamb. • ZIP! - Defeat The Lamb in under 20 minutes. • It's the Key - Defeat The Lamb without taking Hearts, Coins, or Bombs through the entire run. Letting certain familiars (e.g. Bum Friend, Dark Bum, Bumbo or Lil Portal) or bosses (e.g. Bumbino) pick up the consumables fails this condition as well.'"`UNIQ--ref-00000000-QINU`"'. • Once More with Feeling! - Complete a Victory Lap by defeating The Lamb. • Missing Poster - Defeat The Lamb as Isaac. • Maggy's Faith - Defeat The Lamb as Magdalene. • Abel - Defeat The Lamb as Cain. • Curved Horn - Defeat The Lamb as Judas. • ???'s Soul - Defeat The Lamb as ???. • Black Lipstick - Defeat The Lamb as Eve. • Samson's Lock - Defeat The Lamb as Samson. • Demon Baby - Defeat The Lamb as Azazel. • Pandora's Box - Defeat The Lamb as Lazarus. • Mystery Sack - Defeat The Lamb as Eden. • The Soul - Defeat The Lamb as The Lost. • Succubus - Defeat The Lamb as Lilith. • Karma - Defeat The Lamb as Keeper. • Locust of Death - Defeat The Lamb as Apollyon. • Brittle Bones - Defeat The Lamb as The Forgotten. • Alabaster Box - Defeat The Lamb as Bethany. • Damocles - Defeat The Lamb as Jacob and Esau. • Godhead - Earn all 5 / 9 (except Ultra Greed) / 10 / 12 Completion Marks on Hard mode as The Lost. • Mom's Lock - Defeat Isaac, ???, Satan, and The Lamb as Tainted Isaac. • Holy Crown - Defeat Isaac, ???, Satan, and The Lamb as Tainted Magdalene. • Gilded Key - Defeat Isaac, ???, Satan, and The Lamb as Tainted Cain. • Your Soul - Defeat Isaac, ???, Satan, and The Lamb as Tainted Judas. • Dingle Berry - Defeat Isaac, ???, Satan, and The Lamb as Tainted ???. • Strange Key - Defeat Isaac, ???, Satan, and The Lamb as Tainted Eve. • Temporary Tattoo - Defeat Isaac, ???, Satan, and The Lamb as Tainted Samson. • Wicked Crown - Defeat Isaac, ???, Satan, and The Lamb as Tainted Azazel. • Torn Pocket - Defeat Isaac, ???, Satan, and The Lamb as Tainted Lazarus. • Nuh Uh! - Defeat Isaac, ???, Satan, and The Lamb as Tainted Eden. • Kid's Drawing - Defeat Isaac, ???, Satan, and The Lamb as Tainted Lost. • The Twins - Defeat Isaac, ???, Satan, and The Lamb as Tainted Lilith. • Keeper's Bargain - Defeat Isaac, ???, Satan, and The Lamb as Tainted Keeper. • Cricket Leg - Defeat Isaac, ???, Satan, and The Lamb as Tainted Apollyon. • Polished Bone - Defeat Isaac, ???, Satan, and The Lamb as Tainted Forgotten. • Expansion Pack - Defeat Isaac, ???, Satan, and The Lamb as Tainted Bethany. • RC Remote - Defeat Isaac, ???, Satan, and The Lamb as Tainted Jacob.

• The Lamb can be reached before The Negative is unlocked by taking the trapdoor in a Black Market from Sheol if one shows up.
• The Lamb can be reached before The Negative is unlocked if a Sacrifice Room is used 12 or more times.

• Despite Jesus Christ often being referred to as the "Lamb of God" in the Bible in the books of John and Revelation, The Lamb in this scenario most likely refers instead to the ram that was sacrificed in Isaac's place in the story of Abraham and Isaac, which this game is based upon.
• Upon defeating The Lamb, the song that plays in the credits changes to Hush (Jesus loves uke)
• The music that plays during this battle is titled The Fallen Angel.[1]
• The Lamb is likely a reference to the name of the original Binding of Isaac's DLC expansion, The Wrath of the Lamb. Due to the absence of any mention of a Lamb in the original game, this may be the character eponymous with The Wrath of the Lamb expansion pack.
• The Lamb's battle portrait depicts him with dark grey bones, but in-game the Lamb has white bones.
• The Lamb shares its name with a level from Edmund's previous game Super Meat Boy.
• The Lamb is one of the three bosses that can dim the room (making a temporary Curse of Darkness effect). The other bosses are Dark One and The Adversary.
• During an AMA stream, Edmund McMillen confirmed that The Lamb is "Isaac, dead, as a demon," and that it represents "his evil side". [2]
• The Lamb is male.