I have a suggestion regarding this weapon if you want to hear it:
Keep the teethy stuff, but turn it into a cursed gauntlet that the player wears, it bites into the players arm, curses it and morphs the arm itself into a weapon that shoots the green cursed goop or something similar.
Could have some fun sounds, like this:
https://www.youtube.com/watch?v=VXvIjR8RWMs
or maybe a bit fleshier.
You could even do fun stuff like 1hp of life is one shot. Would make for an interesting risk / reward thing.