I have three pieces of the FotL armor on my hunter (arms, chest, and cloak). I think it's a cool-looking set, so I was infusing it to usable levels, and I noticed only the chest piece has a masterwork slot. The gauntlets and cloak do not. I just checked, and my Dragonfly Regalia set has masterwork slots on all pieces, so I was just wondering if that's a bug, or if it's intentional. Edit: Update with more info. I've figured out why some pieces do, and some don't have masterwork slots. I also have three pieces on my Warlock (gloves, boots, and bond). In both characters' cases, I bought the gloves and class item with bright dust, and the chest and boots dropped from engrams, so it seems if you buy the armor, it doesn't have a masterwork slot, but it does if it's an engram drop. The question of intentional or a bug still stands, though.