For the new dungeons of Scions of Ithelia, I bought 6 of the 5 key boxes. (Urgalarg is not offering the 1 key random, fix it!) opened up, all light and medium pieces, then again and again, for something around 16 boxes all light and medium pieces.
I was staring at my inventory list, wondering, thinking, asking, why would it be that? If they're to be dropped with uniform probability, the chance of not getting any heavy piece is (1/3)^16~2.3E-8.
THIS IS NOT RIGHT!!!
Then I looked at the thing I'm wearing, light and medium monster set, which correspond perfectly to the types that I'm getting.
I've heard of something like PvP head-and-shoulder sets drops depending on wearing type, so I just guess it has become the same here as well.
So I unequiped those. for the next 2 boxes, I got 1 heavy. I put it on, then the next box, the last heavy one.
I don't know if it is intentionally to drop that way, BUUUUUUUUUUUUUUUUUUUUUUT, either make it completely random, or just curate it (I'd for sure prefer the latter). This "pseudo-random" or "half-random" or "half-curate" or "pretending-to-satisfy-the-need-of-the-buyer" is just bad bad bad.
If there is indeed such a functionality behind those, and if you don't make it clearly known to all, just remove it completely.