Welcome Ogre92
If you try the Stunt Roll (Fantasy AGE, Modern AGE, Dragon AGE) you will see it throws 2 black and 1 red dice.
The roller Im currently working on for Open Legend RPG throws a Blue plus (potentially) multiple black and green or black and red or just black dice.
Try the following command:
/die 1d4+1d1004+1d2004+1d3004+1d4004
in the chat window
Those same prefixes - 100 thru 400 work for d4 thru to d20.
You can also use the Dice pool to add dice by dragging and dropping or by command: /pool 2d20010
You cannot selectively swap dice out of a pool though.
You can either remove all the dice in a particular slot or all the slots - but not individual dice in slots...
Try it and what Im saying might make more sense....
This stuff applies only to the MoreCore ruleset. Those extra coloured dice are not in CoreRPG. The Dice Pool is available for CoreRPG as an extension by ianmward.

