I have to admit that Mugino looks a little more threatening than Bowser. It helps that energy balls typically trump fire when it comes to destructive power. Bowser wouldn’t be able to get close enough to Mugino to launch any attacks because of her laser ability. She can protect herself from close attacks and also attack people from long range. Her ability has no weaknesses that Bowser can exploit so he will have to take the loss. Mugino wins.