I feel guilty making so many asking threads lately but I'm working thru Blacktober pieces still and today's obstacle is trying to find a convenient way to render a cliff/cave wall. For context this is my sketch

The idea for the space they're in is something akin to those funky low poly rpg dungeons with the rock walls and torches and hidden treasure rooms or bosses. It's supposed to be like a post fight looking over their loot bit but i'm once again figting backgrounds with trying to figure out how exactly i should render the cave walls
Ideally I'd like to find some kind of texture brush that can easily mimic a cracking pattern for me to use for the cave wall and then something like a stone/rock/debris brush i can use as a break between wall and floor. So like..the idea and at least one method to accomplish the look i want exists in my head its just..finding the resources ;;
any help or tips are welcome tho as it's been really interesting to hear perspectives on how to approach bgs and such