My headcanon for Zo-Zla Halawa.

He is actually our Godzilla's father. He killed multiple Mothras and absorb their DNA to become immortal. But was stopped by an army of Great Apes and Gojis. One of thoese Great Apes was Skar King, after learning of what a Goji was capable of he started the Great War. That's my headcanon for Zo-Zla Halawa.