This is my first ever submission for something like this I am terrified of the deep ocean, and I'm convinced alien monsters are living there, so, welcome to my nightmare lol.

What I imagined:
Long ago, a diver entered the abyss and never returned. His airhose had been ripped from his helmet from something unseen, and he drowned alone in the darkness.
When a recovery dive took place, his helmet was found intact, but detached from what was left of him. Inside, the creature took root in his remains. After it consumed him, it grew strong enough to breach the helmet and hunt unlucky prey from its new home. While it grows and feeds, its mother is always watching.

Hope you enjoy!