OK so dont know how to explane it but i will try. All aoe skills / debuffs have range, lets say some aoe dmg have 200 range to dmg or stun, if mob who run to player are for example 250 range, and player start use aoe, and mobs come to 200 and player hit, this mobs never get dmg or debuf. Its mean whan if someone train lots mobs he must stand and wait untill all mobs are on 200 range. cose in run mode using debufs or stuns, never work on mobs / players who come to this location where stun is working.