As has been pointed out before, this is random. There is no guarantee you will ever get a drop. The first time I ever used Three of coins, I popped 2 coins & got an exotic on the first Ultra boss I killed. I then didn't get another for over a week. Last nite I popped 5 coins & got another exotic. It's just random. No rhyme or reason. Just keep plugging - it'll happen eventually.
English
-
I've now used 46 Three of Coins and 0 exotics since I bought them from Xur on Friday morning. That's about 12 strikes a day.
-
Don't know what else to say except - IT'S RANDOM. Just like buying the Exotic Engram from Xur & getting an item you already have - IT'S RANDOM. Random means you have a chance but no guarantee, whether you use 46 coins or 100 coins. If it's too frustrating to deal with, then don't use them anymore. Otherwise, except it for what it is & keep plugging like the rest of us. I wish I could be guaranteed an exotic if I used a certain number of coins, but I'm not. I even tried 10 coins once to see what would happen - no dice. Hang in there.