Also spoilers for Monsterverse Declassified (majorish) and Kong: Survivor Instinct (minor)

Lahamu is Tiamat’s daughter, who first (and currently only) appeared on the game Kong: Survivor Instinct. It’s not known how Tiamat got her offspring

Despite being a member of Tiamat’s species, she looks vastly different from her mother, even more so since Tiamat herself evolved to have a different appearance by absorbing other creature’s dna

The other creature being none other than Asterias Abzu (or just Abzu), a giant starfish with a gaping mouth, 3 toothy tongues, green suction cups in place of tube feet, armored plates with pink crystal like spots scattered throughout, and a pink corrosive liquid

When Tiamat absorbed this titan’s dna, she grew 4 legs, lost her tail fluke, and had vastly different fins on her back, having her adopt a pink color scheme instead of blue

Where does this take us? Abzu may be Lahamu’s father. Let’s start with overall appearance

She has many attributes that can be associated with Abzu that Tiamat, evolved or not, doesn’t possess:

Multiple tongues

2 Legs

Big mouth without beak like tip

In the mythological perspective, Abzu is the name of Tiamat’s husband and fathered many kids including Lahamu. Knowing Monarch, they tend to name their kaiju on myths. They do not have to be 100% myth accurate and have the slightest correlation, such as Scylla having 6 legs instead of 6 heads and Abaddon still having an evil bug army except they’re spiders instead of a locusts

Instead of being a loving couple, Tiamat and Abzu had a fight to the death and I believe that absorbing his dna may have lead to one of the these things:

Got pregnant and had Lahamu halfway through her transformation

Already was pregnant (likely through parthenogenesis) that also absorbed Abzu’s dna

Anyways that’s all just a theory lmk what yall think

Also here’s my older theory on Mothra and Abaddon: https://www.tumblr.com/shellvine/780962550196109312/monsterverse-mothra-solo-film-idea

UPDATE: it has just come to my attention that Lahamu is probably bio engineered instead due to a new book so this theory may be invalid now