What's nice about these is not only can you camp during Devil Manta down-time but you don't have to be THF because Arachne is guaranteed to drop 2-4 skins, even with TH he tends to stick to 2.
The stupidity of some ppl that play this game is beyond me...I farm these regular, i never have a problem selling these, sometimes they sell immediately. So why on earth drop the price by 10k... idiots!!!!