Dear friend, thanks for the brilliant playing! You even have finished this very hard stage without taking damage. It is a miracle👍I suggested the strategy that finishing the battle with Trace as quick as possible to prevent she heal over time. But now I think quick strategy is not necessary. The rule of Trace heals is the following: she heals 6 ticks' health at the first time, then heals 6, 5, 4, 3, 2, 1 health in order, then she does not heal any more. I noticed that in this video, you already have killed her as quick as possible, but she still healed 6+6+5+4 healths. It means that even if you fight with her in the slowest pace, you only need to treat her 3+2+1 extra healths, but in this slower pace it will be much safer and has less possibility to take damage. Of course, the drawback is that since you will face her 6 extra healths, it also brings possibility to take damage. So you could choose the better strategy in your mind to take less damage.