Are you talking about post-September 1? Kherson, Izium, Lyman?
100K is a mind-numbingly stupid number- several times larger than the total number of AFU forces in the northeast offensive, which was 5 Brigades- about 15,000 troops.
I don't know how many casualties the AFU took in the Izium or Kherson advances, neither side publishes the numbers. Estimates based on the visually confirmed equipment losses suggest something like 9.5:1 in Ukraine's favor in Izium. The Russians lost hundreds of pieces of equipment, including brand new T-90M tanks.
Kherson is a little different, the terrain is flat and open. It was probably not so one-sided, the Russians were in defensive positions and had at least some artillery support. But they collapsed quickly, which means they did not inflict heavy damage on the AFU.
The highest casualties are happening around Bakhmut. Those fields are just littered with corpses. Wagner convict recuits and mobiks, they are sent in to occupy trenches and draw AFU artillery fire. Then the Russians target the Yook arty, wait a while, and send another batch of cannon fodder forward to see if the Ukrainians are still there. This has been going on for 4 weeks now with no positional changes. It's just mindless carnage, but the AFU are still taking casualties from the Russian SPG's.
There is a video released a few days ago, you've probably seen it. Russian soldiers under artillery fire, desperately trying to crawl into any hole and curl up, one guy is furiously crossing himself over and over. That's Bakhmut. Those guys are taking 80-90% casualties.