The Old Code said:
>> I'm still having issues with characters wanting to attack creatures outside the set range (i.e. '3'

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>> They literally attack everything within the detectable range of ElTank.
I cannot repro this . . . but it almost sounds as if whatever area you are hunting is confusing Tanks range scaler. (There are two scales: outdoors and in dungeons) Could you post (or PM me if you prefer) where exactly you are hunting when you see this happen?
And can you try hunting, say, the 125+ Eater dungeon or the hills around Danby's Outpost and see if it still happens? Cause that's where I just tested and it works fine for me.