I often have players, especially those new to D&D or new to Roll20, who make mistakes when leveling up their characters using the Charactermancer. In this case, I need to go through the process of manually editing their sheets in order to undo the level up and allow them to correct it, or if the mistakes are especially bad, create a whole new sheet. This process can be especially frustrating for players, and is time consuming for me. A way to "step back" in the charactermancer, to take back one or more levels from the character, would be a huge benefit for newer players who are prone to making mistakes.