I was wondering if ancient shell was a tradable material. I haven't done any of the totodrone events but I would very much like to craft one of the "buster" guns. I looked in the auction house and there were none being sold. In the case that they are tradable, I would urge any willing sellers to contact me either via this thread or in-game message.
They are not sellable, sadly. The only way to get the weapons/shields from those events is either to buy the weapons, or wait untill an event to craft them