ToME: the Tales of Maj'Eyal

Can someone explain this, in 1.4.5 update.

Assuming you mean the diminishing returns on flat damage reduction; since I'm not aware of any new damage resist.

Its the same formula as powers and saves, but with a different step level.
So 40 raw points = 40 reduced damage.
80 raw points = 60 reduced damage.
120 raw points = 80 reduced damage.
160 raw points = 94 reduced damage...

are you certain these numbers are right?
So 40 raw points = 40 reduced damage. -- there is 1 to 1 basically
80 raw points = 60 reduced damage. -- after 40, you get 2raw to 1effective
120 raw points = 80 reduced damage. -- and... again 2 to 1?
160 raw points = 94 reduced damage... -- and here its 14...

unless its...
first 40 give you 40...
then next 80 points adds you 60, making it 100...
no, these numbers are too big already.

next 80 increases it to 60? that would be 4 to 1 ratio, what the hell is happening here?!

I think its right.

So what talents or equipment egos would use this new formula?

The big offenders (why this got nerfed so hard) are the Whitehooves Racial tree, the Gunslinger's Avoidance tree, and the Sawbutcher's Furnace tree, plus the new Constitution Prodigy.