You can do both of those things, the second thing is called "exploding dice". Here's the first: /roll {1d20 + @{selected|ToHit}}>@{target|AC} Where "selected" is the currently selected token and "target" is the target of the attack. Of course, the target token has to have an attribute called AC and the selected token should have a ToHit attribute (or if you'd rather them have a separate BAB and modifier attributes). Exploding dice are as such: /roll 3d6!>5 In this example, any dice that are 5 or higher "explode", or have an additional die rolled for them. You can simply put {3d6!} to only roll on the highest on the given die (a six, in this case).