A common misconception flooded both the Jedi and Sith. That the flames belonged to the Darkside. The Grandmaster herself had shown them how untrue that was. Rather than simply cut the plants, Draugr super-heated the air around his legs. It was one grain of sand from tipping into a conflagration. Caris provided the tipping point. Draugr built a scorching heat around his legs. As the Sith Lord was focused on cutting the branches and heating the air, Caris acted.
Timing his working of the Force at the moment the Sith Lord was most focused. As the air reached the temperature to burn plant life...he struck. It was a simple act. Just push the air over the limit. The air was already scorching hot around his legs. In an instant, scorching hot became boiling flames.
The air around Draugr legs became a fire which tore at his legs and lower abdomen. Caris quickly took hold of the flames to press them into Draugr’s body and burn through whatever flesh existed. Draugr foolishly failed to engage again which left Caris free to do as he wished. He took a step back as he set the fire. No need to get caught in it. It would be extremely difficult for Draugr to escape unscathed as the hot air turned to fire in an instant and that hot air was all around his legs. One Sith was on the ground. Another would soon follow.
@Mockingjay @Reylo4evr @Scoobert