natural evasion?

[b1indpuma]

i've noticed a few servers seem to have this check that compares the mobs level against yours and adds artifical evasion for each level you're higher than it. for instance, on default arcemu core, a level 80 will still get hit by something that is level 10 - where on these other servers, a level 50 or 60 would have an incredibly hard time hitting a lv80 using the same gear as before. is there a script or a different core (like hearthstone?) that would allow this? a reply would be much appreciated.