Just look at the first post here where it has screenshots of how she was on release and compare it to how she is now…
Stun immunity → Stun converter
Hell thunder nova (SS) 5 charges needed → 4 charges needed
Bloodcrave → Double bloodcrave
Poison immunity → Venom ward (adds hold ground) then later → Alloy soul (adds robot type and +100% defence if robot teammate)
She became a far, far better sweeper thanks to stun converter and double bloodcrave. She also naturally tanks far better (HG is amazing when she has a full heal move) and with a robot becomes genuinely super tanky.
She was underpowered on release, not a moveset worthy of a mythic. Started at D tier then crept up more with the (3?) buffs.
If you want to track monsters over time you can check out Tier list change log and search in that topic for a monster name. It will come up with all the posts it’s mentioned, which generally aligns with when it was buffed/nerfed and then either it will detail the change that happened there or you can cross-reference the update number with KD's Version update history to go see exactly what was changed. I don’t always mention every monster that was tweaked, but any very notable change should be in that tier list change log.