I want to say first that i really LOVE this artwork that you have done! I like the perspective that you have created with ur piece. Mostly the warrior...his back is turned toward us giving him a mysterious effect and the long, flowing cloak shows a certain elegance for the character. (amazing!) If it weren't for ur description in the comments, a viewer would look at this piece from a couple angles: 1, this could be a warrior summoning the beast or 2, the warrior was there to kill it.
Ur beast is great! the shadows the you've created does give the creatures face a eerie cast the playing with its demonic face. Which i love the size of the beast! A monstrosity!!!
With its pros there are cons. hope my criqtue helps you.
So the title you gave it was "In the Cave" To me they don't look like their in a cave. To me... the warrior is on a cliff with the wind flapping the cloak about, looking in the distance as the beast rises out of the cloudy mists and it seems like its dusk. So i'd tweak the name or if u can change it, change it. If not then keep a heads up when u create ur next scenary.