This is Amanaman.
Confound that Amanaman! Of all the trippy creatures born of the Star Wars universe, this guy has to take top prize. Supersized leech? Tempura with an attitude? Tricky to try and ID the inspiration behind Amanaman. Whatever the case, and despite the fact that actually seeing him on screen in the Return of the Jedi is nearly impossible without hitting ‘pause’, his twisted legend endures. A rare and truly awesome vintage action figure.

I can hardly understand what the heck is that.
Nice one. He looks genuinely creepy, which I suspect he was supposed to be. After all, he appears to be some sort of bipedal gastropod with fangs who collects the skulls of his victims. Or something.