My worst moment came while leveling up my Hunter. I had been grinding on the strike list all day to earn my first 75 marks. When I finally got them I bought the Gravebreaker sleeves. I was still pretty noobish at this point so it didn't occur to me to just give my Hunter one of my Titan's Commendations, and get chest armor instead. While out on my very next patrol I acquire a legendary engram. When I decrypt it, it turns into Astrolord Grips. Ratings wise the same thing except better Intellect and Discipline. All I could do was face-palm...and equip my Astrolord Grips.