Edit conclusion: look to the bottom for the ideal solution for easiest setup. Alright, this took a little puzzling out, but I managed to make it work - though it requires a bit of setup. First, add this to both the other attack modifiers field and the additional damage field of the attacks you want: -?{Sneak attack?|Yes,?{Powerful Sneak?|No,0|Yes,2}) }} {{roll04=@{prefix}@{character_name}|level@{level}sneak}|No, } Next, create the following attribute: prefix %{ Finally, create the level-based sneak damage abilities - you can either create one for every relevant level, or change them as you level. I set this up with the set-up-once option. level1sneak [[[[{[[1d6]],?{Powerful Sneak?}}kh1]] [SNEAK ATTACK]]] level2sneak [[[[{[[1d6]],?{Powerful Sneak?}}kh1]] [SNEAK ATTACK]]] level3sneak [[[[{[[1d6]],?{Powerful Sneak?}}kh1]]+[[{[[1d6]],?{Powerful Sneak?}}kh1]] [SNEAK ATTACK]]] level4sneak [[[[{[[1d6]],?{Powerful Sneak?}}kh1]]+[[{[[1d6]],?{Powerful Sneak?}}kh1]] [SNEAK ATTACK]]] level5sneak [[[[{[[1d6]],?{Powerful Sneak?}}kh1]]+[[{[[1d6]],?{Powerful Sneak?}}kh1]]+[[{[[1d6]],?{Powerful Sneak?}}kh1]] [SNEAK ATTACK]]] And so on, adding +[[{[[1d6]],?{Powerful Sneak?}}kh1]] for every odd level. EDIT: A less setup-intensive way to do this, if you are the GM or can bug your GM to make a table for you: Have a rollable table named "powerful-sneak", containing items 2,2,3,4,5,6, simulating the die roll, and then have the following in both the other attack modifiers and the additional damage fields: ?{Sneak attack?|Yes,?{Powerful Sneak?|No,}} {{roll04=[[[[ceil(@{level}/2)]]d6]]|Yes,-2)}} {{roll04=[[[[ceil(@{level}/2)]]t[powerful-sneak]]]}|No, } EDIT2: Thanks, RainbowEncoder, for the trick! This version only needs to be added to the Other attack modifiers field and to the Additional Damage field, no other setup needed! ?{Sneak attack?|Yes,?{Powerful Sneak?|No,}} {{roll04=[[[[ceil(@{level}/2)]]d6]]|Yes,-2)}} {{roll04=[[{[[ceil(@{level}/2)]]d1*2+[[ceil(@{level}/2)]]d6}kh[[ceil(@{level}/2)]]]]}|No, }