From Binding of Isaac: Rebirth Wiki
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| The Womb|
Behavior[edit | edit source]
- Hops around the room randomly and shoots tears in all directions.
- Once enough health is depleted, it will split into two medium versions of itself, which shoots 6 tears in all directions.
- These two medium blastocysts each split into two smaller forms, which shoot smaller tears in 4 directions.
- When all the parts of the blastocyst are defeated, they will become a bouncing Embryo that does contact damage.
Blastocyst is perhaps the least complicated boss in this chapter, having essentially one attack that gets weaker for each split. Any sort of piercing tears or items such as Technology 2 or Brimstone can defeat this boss extremely quickly.
Gallery[edit | edit source]
Trivia[edit | edit source]
- An embryo is called a blastocyst when the differentiation of cells within a morula finally begins, usually 4-5 days after the fertilization of an embryo.
- It is very common for the second level of the boss to spawn as normal enemies in rooms. On even later floors like Sheol, the full boss can even spawn as a common enemy.
- If Blastocyst is killed on spikes, none of the smaller versions will spawn. This can also apply if a very large amount of damage is dealt very quickly to any of the phases.
- This can also happen if Blastocyst is killed while still having a debuff that actively harms it (e.g. poison, fire).
- Upon killing a blastocyst, it seems as though, for a split second, an audio clip of someone's voice can be heard. To better hear it, listen with headphones without the music.
|Achievements||Attributes||Bosses||Cards and Runes||Challenges||Chapters|
|Chapter 1|| Blighted Ovum • Dingle • The Duke of Flies • Famine • Fistula • Gemini • Gurdy Jr. • Gurglings • The Haunt • Larry Jr. • Monstro • Pin • Steven • Widow |
Dangle • Little Horn • Rag Man • Turdlings
|Chapter 2|| C.H.A.D. • Chub • Dark One • Gurdy • Gurdy Jr. • The Hollow • The Husk • Mega Fatty • Mega Maw • Peep • Pestilence • Polycephalus • The Carrion Queen • The Wretched |
The Forsaken • The Frail • The Stain
Big Horn • Rag Mega
|Chapter 3|| The Adversary • The Bloat • The Cage • The Carrion Queen • The Gate • Gish • Loki • Mask of Infamy • Monstro II • War • The Wretched • Mom |
|Chapter 4||Blastocyst • The Bloat • Conquest • Daddy Long Legs • Death • It Lives • Lokii • Mama Gurdy • Mom's Heart • Mr. Fred • Scolex • Teratoma • Triachnid|
|Chapter 5||The Fallen • Isaac • Satan|
|Chapter 6||??? • The Lamb • Mega Satan|
|Greed Mode|| Ultra Greed |
|Chapters 1-4||The Fallen • The Headless Horseman|