MM3 gave us a few variations on the plain old troll which, incidentally, got +1 LA for a total ECL of 7 in a much earlier thread. Looking back, I wonder if by modern standards it'd have been given +0 instead, and I guess there's no way to know for sure.
Anyway, the cave variant has a total of 9 RHD, and comes with Large size, two 2d6 claws, and a 1d8 bite. Their stats are par for the course: high strength and constitution, abysmal (as in, barely-sentient) intelligence, and mid-low stats elsewhere.
Notably enough, cave trolls get Pounce. They also enjoy Rake, Rend, Improved Grab that works off bite, and the ability to daze a foe it hits with both claws. It's a strong status to hit foes with, but having to use either a mouthpick weapon or no weapon at all worsens it considerably. Cave trolls do not have regeneration, and get Fast Healing 8 instead.
Cave trolls have enough muscle to make completely reasonable characters, even if they are lacking in terms of versatility. +0 it is.