She would launch from time to time wind blades and fireballs against them, and it was enough to keep them at distance as they had to keep moving to avoid her attacks.
Sometimes she also use the body of the one she was fighting with to shield her from their attacks. But suddenly, she saw an opening; maybe they weren't careful enough.
As the two kids still using their vines wanted to attack her from behind, they both used different directions to launch their attacks and stopped protecting themselves. If she could use her speed combined with her wings, she would be able to push them out of the combat zone.
Willow then waited until they were ready to attack her, and then she kicked the kid she was fighting in the stomach, sending him flying outside the circle that delimited the combat zone.
Then she used her maximum speed to dash once more towards the two kids left.
The vines that were supposed to immobilize her broke as they hit each other, their target already far from them.