WE BEGIN TO ROCK...STUDY, STUDY ROCKIN ALL NIGHT LONG

This is the fun part. I like to look for a brush I that Zbrush hides away as trim. My 2 favorites so far is Trim Dynamic and Trim Smooth Border. With those two I can achieve rocks similar to on the right with some effort. Trim Smooth Border has a bit of a learning curve but once you get used to it, its pretty neat. I don't use the ALT function on it.