Embryo

Embryos are monsters that hop around the room, dealing contact damage. They are relatively harmless as they do not move much from their position and don’t target the player.

Trivia

 * Embryos count as the Blastocyst boss. Blastocyst still splits into Embryos.
 * Embryos bear a strong resemblance to Spewer: the star of the game Spewer which was also created by Edmund Mcmillen, the maker of The Binding of Isaac.
 * In the original The Binding of Isaac, they have health bars (like mini-bosses or bosses have).
 * Embryos can often be seen in rooms with Blood Donation Machines.