One time long ago I did the nightfall and got a legendary engram, it was only my second time ever completeing the nightfall and all excitedly I immediately went to the tower and ran over to the Cryptarch (I had only ever had one or 2 Legendary engrams ever at this point so I was damn excited) decrypted it and what did I see pop up... 1 lowly Mote of Light. Most disappointing and anticlimactic feeling ever.