also i ahve a superior cryptic axe. 13% enhance damage. is this useful?
You want polearms with 4 sockets.
So nah, tresher has no worth.
Cryptic has max 4 if i recall correctly? Might want to look it up in wiki. If yes, non-eth useful for selfuse, eth has trade value.
thank you pachu for the detailed reply. 
atleast i know these things have no value. hHa
If you find superior 15 Ed eth giant thresher, I think you can sell it for BoTD base.
Non-superior one you could probably sell as well, but you have to find a buyer first.
Maybe a druid or barb will buy it for breath of the dying. But I wouldn’t expect too much for it. I’ve looked at some trade sites and they go for Fal or PGs IF they’re sold at all.