like the title how the frick do i get into the temple of the serpents, i spoke to "kol the heretic" or who ever he is, and i recieved a key from him. where do i use this?

Face the temple now go left and muck around until you find an area that has water and a grate that you can swim thru. Hope you have cure poison!

PS you will find a key hole that appears to be for nothing (spirit eye is a good spell for this place) and it will open a secret room for Kerah statue.

Face themple. Turn to your left and you will see a path leading south. You'll have to wade through some water and find a path that lead to a cave with some iron bars over the opening. Go underwater and swim through.