Well it had promise, but dropped the ball pretty quickly again.
The only thing making this any different from the usual "MC gets a useless power that turns out to be OP and then takes revenge on the people who ostracized/betrayed him" garbage is that the MC is female this time. Slightly more thought was put into the reason for the betrayal this time at least, since it was for an actual reason rather than "lol i dont like the hero because he has black hair xdddd" or something stupid.
A few minor changes would have made this story much more original :
-They do more testing on the hero's power. Yea, she can boil water...but perhaps she can boil other things too? What if she could boil a lake from a huge distance away? You dont need to be a genius to try testing this. Lots of ways it could be useful.
-Even if the hero's gift is useless, she can still level up via killing people. So this is supposed to be a tyrannical kingdom right? Round up a few hundred criminals for her to execute, and voila you got a girl whos way stronger than any soldier. Then you just use her till she dies in combat and get a new hero.
-Have the MC run away on her own because she doesnt want to fight anymore, THEN send people after her. Sending people to burn down her whole village before turning her into an edge lord that tortures people to death makes it really obvious that the author just wants to write an edgy revenge story where the MC is justified in whatever she does.
A normal girl turning into an edge lord that just wants to torture people to death, in less than an hour, really breaks suspension of disbelief here. Killing them in self-defense was fine, but torturing the last guy to death didnt make any sense unless she was already a psychopath in the first place. You dont turn into a psychopath that fast.
Im quite surprised the author didnt make the soldiers rape anyone in the village, you know just to hammer home the point that the MC is justified in her edgy revenge.