I have only received 1 exotic (land before time Sniper) from anything since the release of this game. And I grind it out just like the rest of the guardians. I have the last word and the plan c, both purchased from Xur. Have completed Atheon and Crota multiple times on normal and hard mode. NEVER have I got an exotic from completion. In fact the only legendarys worth a damn I got was Atheons Epilogue (which since the Dlc is useless). The song of It Yet I received from the Crota raid also. BUT THAT'S IT. Everything else I've purchased, armor included.