In some weird parallel universe, The Goonimal finds himself homeless and looking like a hairy fucking beast wondering around only to find the swamp. It speaks to him, calling him, having been found by another him in another universe.

This is the video of him enjoying a pit but there is not much sinking involved. He jumps in but the video is more focused on him getting fucking slathered, prowling his territory, and jacking like a mad madman.

The swamp slowly devours whoever falls in. Physically the body is swallowed whole but once the swamp gets a host in one universe, it calls to all other hosts in all other universes even if they have never met with the swamp before. And slowly, over time, the swamp devours the fabric of the interconnected lives of every host variation throughout the multiverse.