Need to combine a Cleic and a Half Farspawn Hydra

[Blackhawk748]

I come beseeching the knowledge of the playground! Ok i need a boss character that would combine 2 bosses my party has already faced. The first one was The Mistress, a Cleric of Nerull, the second was Korag a Half Farspawn Cryohydra that works for Nerull. Now i know i could just use a hybrid of them but i'd prefer to just find a creature that i could use to represent them. (after all Nerull is punishing them for failure)

The party is lvl 8 and consists of a Druid, a Sorcerer, a Knight, and a Bard

[Chilingsworth]

Well, the closest thing I can think of is the shreiking terror, from MM3. It's actually a hybrid of a hydra and a vargouille (well, actually a bunch of them, I think.) It might be refluffable for your purposes, though.

Also, you might want to modify it, I believe it's a CR 13 monster as is.

EDIT: The CR 13 version is the 10 headed terror. The 5 headed version is CR 10.