Holy crap, the Alchemy Lab is puzzling. I have gold on every other room, and platinum on 10 of them, but I still don't have more than bronze on the Alchemy Lab.
My biggest problem with this game is that it is not at all transparent how Fumes and Vessels work - but if you don't figure it out, you won't kill enough of them to unlock them in the bestiary and find out how they work! The reason is that "enemy that does a self-destruct attack on death" is a very common trope, as is "enemy that releases smaller enemies on death" - so when I saw Fumes or Vessels exploding, it never occurred to me it was triggered by getting too close - I thought I had killed them! I only unlocked Fume in the Bestiary after many, many games (way after having unlocked Seeker in the Bestiary, e.g.), and still haven't unlocked Vessel - I only know now Vessels are also triggered by proximity because I went and looked at the comments.
It's quite annoying how we can't look at the hall of masks without quitting our current game. You should make a way to do that. I got two masks at once, didn't notice (does it even show all the masks you got, or just one, if you get more than one at once?) went to look... and had to start over. Not nice.
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