I was looking at the Trader card and had a few questions. I did look around a bit and did not find answers to these questions.
1. Trader with Ill-Gotten-Gains. If you have a traders in your hand when you play an Ill-Gotten-gains, can you gain a Silver and put it in your hand instead of a copper? My guess was yes, please verify.
2. Trader with Develop. If you Develop a Curse or copper can you gain 2 silvers (question in regard to not having any 1 or -1 cost cards in play)? My guess is no, Develop in the detailed instructions states you will try to gain a card and fail. My question is when does the (when you gain a card) action trigger. Does it trigger when you have already targeted a card to put in your hand or when you are told to gain a card?
3. Trader with Haggler. If I buy an estate and reveal a Trader can I gain a Silver with my second buy? My guess is yes. Because I bought an estate, triggering that I can buy a card less than it. I target my copper, but when I gain it I reveal the Trader and instead gain a Silver. Likewise, can I "buy" a copper and instead gain two silvers? I would still guess yes for the same reason. However, can I buy a Festival and instead gain a Silver and a Jack of All Trades? Silly question, but my guess is yes. Because you bought a festival, that is what the cost is going off of, so even though you actually got a silver you bought a festival and that is what the cost is based on. However, this reasoning would negate my assumption on the buy a copper to gain two silvers. because there is no card costing less than 0 so you have no legitimate target.
I don't know if I am anywhere near right here. Please help me determine proper usage of Trader!