The Binding of Isaac Wiki

The Blighted Ovum (ブライテド・オーブム Buraitedo Ōbumu) is the posthumous version of Gemini appearing in The Cellar and The Catacombs. He has a higher chance of appearing if Isaac has killed Gemini before.

The Blighted Ovum spawns already separated, similar to the green Champion version of Gemini.


The larger sibling appears as a mangled and bloody zombie, with parts of the skull eaten away. He leaves behind a trail of red creep as he moves, which damages Isaac for a full heart. Unlike Gemini, he will constantly pursue Isaac, not stopping for breath after charging.

Meanwhile, the other half appears as an invulnerable spirit, and is passive unless Isaac gets in his line of sight, in which case, he fires a blood beam similar to Brimstone. He tends to stay floating in the area it spawns in, not moving around much. 

Upon death, each half shoots radial blood shots, similar to when Steven is killed.

Champion Variants


Much like Eternal Gemini and Eternal Steven, Eternal Blighted Ovum starts with 1 large sibling and 2 small invulnerable ones. The large one acts exactly the same as its normal counterpart but he can slowly regenerate HP and is able to destroy rocks. The other 2 small ones fire blood beams at Isaac. All of them explodes into fast 8-way bullets on death.


  • If The High Priestess is used on the Blighted Ovum, Mom's foot will stomp on the smaller twin, doing no damage and thus being useless.


  • They appear in the Wrath of the Lamb DLC for the original game.
  • The Blighted Ovum no longer appears in the Catacombs since Rebirth.
  • In medicine, a blighted ovum is a pregnancy in which the early pregnancy appears normal on an ultrasound scan, but later no visible embryo develops. This likely refers to the smaller twin being dead (a spirit).
  • The large bite on the top of the head is on the opposite side on the artwork and sprite; this is probably unintentional.
  • He is also missing his jaw like Daddy Long Legs and Headless Horseman.
Standard Bosses Dukeofflies fullThe Duke of FliesGemini fullGemini260x185-400px-Monstro.svgMonstroLarryjr fullLarry Jr.FistulaFistulaGurdy fullGurdyPeep FullPeepChubChubLoki fullLokiScolex fullScolexBlastocyst fullBlastocystTheFallen FullThe Fallen

Wrath of the Lamb DLC: 260x200-400px-Widow3WidowPin cleanPinMask of InfamyMask of InfamyGurdjrGurdy Jr.VS DaddyLonglegsDaddy Long Legs

Posthumous Bosses 285x230-MonstroII fullMonstro II

Wrath of the Lamb DLC: The HuskThe Husk260x220-The Hollow2The Hollow250x200-Teratoma.TeratomaLokii cutoutLokiiBlighted ovumBlighted OvumCarrionqueenThe Carrion QueenThe WretchedThe WretchedBc BloatThe Bloat

Alternate Bosses 287x265-Steven FullsizeStevenChub fullC.H.A.D.Gish fullGish

Wrath of the Lamb DLC: 200x300-400px-Triachnid boss portraitTriachnid

Harbingers 220x287-Isaac Vs famine edited- noobletkFamineBC PestilencePestilenceBC WarWarVSDeathDeath230x200-Headless HorsemanHeadless Horseman

Wrath of the Lamb DLC: BC ConquestConquest

Final Bosses 250x250-400px-MomMomMoms Heart FullMom's Heart250x250-ITLIVEScutoutIt LivesSatan FullSatan

Wrath of the Lamb DLC: Bc isaacIsaacBC xxx???