I got the explosive poison shard for huntress, which should be pretty good according to the description and  with the gold claws at the side of the icon. But after maxing it, the damage explosion is based on the Damage Stat of the PDTs, which are probably only about 300+, as PDTs are based on poison damage. Which means that the item is pretty crap and not worth being a chaos 4 shard and a waste of gold to upgrade, unless it is based on poison damage. Or it was supposed to be based on poison damage stat and I had wasted my time staring at mobs to count the damage done and missed it.