Since someone made a post about how the Darkling is kinda like Lenin but not really because the only thing they have in common is wanting to overthrow the oppressive absolute monarchy but their reasons and execution were different - I propose an idea: Ulla has the potential to be Lenin in Grishaverse.
Lenin had an older brother named Aleksander, who was killed because he tried to kill the Tsar. What Lenin did afterwards can certainly be counted as one hell of a revenge. So, Ulla finds out that the only decent member of her family, her brother Aleksander, the only one who she shared immortality with, was killed by a bunch of deserters who destroyed his goal of liberating Grisha he spent centuries building towards, and she decides she has finally had enough of allowing humanity to be like this.
Cut to Ulla threatening to drown Ravka and Fjerda, joined by the rebellion of Grisha and otkazatsya who finally realized their saint Queen is an explosive bitch who doesn't have a diplomatic bone in her body and her solution to everything is threatening bodily harm or murder. And that their precious King consort is an idiot who is willing to let people starve and squander the recourses just to shift into cotton economy Ravka cannot assimilate to. Horrible realization that they fell for propaganda and the Darkling's plan was actually better had they not ruined it.
We know Ulla is insanely powerful from being a Sildroher and a Grisha, and I doubt Zoya's measly tidemaker skills can calm down a raid of tsunamis. Her dragon form can't help with anything either if Ulla decides to split Ravka in half again like she did with those northern Fjerdan islands.
