Wither set yes and yes it amps for all and b yes 3 set still pushes back only thing is mreaver doesn't splash effect on off mobs haven't tested if natural splash mobs like sora dandoline etc do late game I'd dive GiB mreaver and full set and as I recall my main would do around 60% other thing is stunners plus wither doesn't seem to work well since I noticed theyed stay put instead of moving backwards as for rhosthose supports think might have to do with armor is my guess with 5 sec attack speed much better towers to use to wither with I forget how wither set works on bear hunter I know he can frozen with ice set but forget how wither works
