Recently I just read some post about people not liking the current cave-in troll mechanic which causes too many cave ins if they are ''abused/glitched'' and I thought :
Why not have the troll punching tiles without causing cave-ins AND instead having it destroying the quality of rocks and ores in a X radius if they destroy too many tiles and if they can't pathfind themselves. Could be sad if theres like some rare ores but could it make the game better? But... It also dosen't make sens it wouldn't cause a cave-in..
Just sharing my thoughts/idea on this.