She is already pretty grounded if you just take away her powers...
I mean you could make her into a bio terrorist that wants to kill humans on mass with a crazy poison she made from different plants.
that would basically be a Bond villain, and pretty grounded.
Gotham is razed to the ground by a literal earthquake. Batman is trapped alive in his collapsed Batcave, and getting out alive will be his greatest test yet.
Sub-terfuge... played by Sylvester Stallone. Runs an 'adventure' company for billionaires, but sabotages them on occasion in order to murder the do-gooder billionaires that want to make life better for everyone instead of just billionaires. This is also a new Batman origin story as he kills Bruce Wayne's parents on an excursion to the long sunken Supermanic (there's kind of a backdoor Superman reboot thing here because Superman is like... trapped in the wreck in like... I don't know, a Kryptonite holding cell? Is that how Superman works? anyway he's stuck there for like a hundred years, the Waynes were going to rescue him but they don't because they get murdered by Subterfuge)
Coomer... played by Timothy Chalamet. Stepson of a billionaire, lazy spoiled 'music producer' with no talent. Jealous of Bruce's inherited wealth he conspires with Subterfuge to murder his own parents. The plan seems to be a success but while doing some suffocation-play with a paid OnlyFans model he receives a call from the lawyers informing him that his stepfather is indeed dead but that the family dog was the only one named in the will, and the will is ironclad because they are billionaire-level lawyers. Receiving this call basically breaks his junk, and he can no longer achieve an erection. This all makes him even more angry with Bruce Wayne. Also he walks around with big stupid headphones that are always playing a shitty 1-5-6-4 punk rock power chord progression.
Would have to be someone who is a master of disguise, and has maybe created some sort of paralysing toxin that can reshape the muscles on his face to resemble other people.
The Robert Pattinson-starrer ‘The Batman’ had already announced its sequel for 2025.
glamsham.com
So Freeze or Clayface. I hope it has a sympathetic epic Mr Freeze/Nora story. I think it could work and be grounded in reality if Mr Freeze had severe horrific frostbite from a lab accident. Something like this;