The Baby Kaiju appears to bear a general resemblance to the mature Otachi from which it was birthed. It has a short snout and large, round eyes, framed by a skeletal face. Its skin is thin and slick with afterbirth and translucent. Its general underdevelopment suggests it may have gone on to develop the same attributes as the mature Otachi.
After Gipsy Danger kills Otachi, Hannibal Chau and his crew of poachers move in to harvest the parts and the brain. Newton Geiszler realizes too late that Otachi is pregnant, and Chau and his crew are attacked by the newborn. However, the newborn was ignorant to the fact that its umbilical cord was wrapped around its neck, and chokes itself in its frenzy. Hannibal also speculates that its lungs were still underdeveloped, so it couldn't breathe well on its own.
When Chau moves in closer to the newborn, it rises and swallows him whole before finally dying. Geiszler and his skeptical colleague, Hermann Gottlieb, use the Pons to Drift with the Kaiju's brain and discover the secret controlling the flow of Kaiju through the portal. Later, Chau cuts his way out of the creature, seemingly unharmed.
- During a mid-credits sequence, Hannibal Chau is shown slicing himself out of the belly of the newborn. He is seemingly unaffected by the toxic kaiju blood, or the fact he was inside the newborn for quite some time without oxygen.
- The Baby Kaiju was bigger than "two bull elephants".