Every now and then, after completing a stage, you will have another choice to make - and that is choosing one of two skills that improve either your defense or attack, health or mana and so on. The good news is that you can simply reassign those points if you're not satisfied with the picks you have made! Simply hit the button that shows your current player level (in the upper left corner) and hit "Respec" - arrange the skills as you see fit!