Macro help needed

Hello, can anyone tell me if what I am trying to do here is possible with a  macro? The game system gives a base to hit# of 12 subtracting minus modifiers than roll a d20. For example:  A warrior has a To hit number after modifications of 5 (which is 7 pluses)  so if he rolls a D20 and rolls a 20 he "hits by 15".  The below Macro works /emas @{selected|token_name} makes an attack and hits or misses by  /roll 1d20- ?{Adjust Hit #|12} Here is the problem ... If the modified number he has is below 0 ... meaning he has say 14 pluses making his base to hit # -2 the macro does not work. Can anyone help me with this issue? Thanks in advance Ara

What is supposed to happen at a negative total? Using basic math, that should then be the opposite (increasing the difficulty as the number becomes more and more negative) , but maybe this isn't what you want. EDIT: I see what's suposed to happen based on Keith's macro.

The parser wants to know that a negative number is negative, and that parses out to --#. I needs to parse to -(-#), so this should work, using parentheses: /roll 1d20- (?{Adjust Hit #|12}) EDIT: Had to fix the formula to give a random 1d20 roll. I had made it static for testing.

Perfect, Thank you so much gents!