Nice idea I like the potion creation and gathering reagents which is nice and straightforward to use.

I did have one issue - sometimes when I brew potions, it also immediately attacks (i.e. it picks up the mouse click to brew the potion and uses it to attack as well) and wastes a potion.

Love it! Potion mechanic is ingenious. I love the mixing and matching of properties. A really great way to combine crafting  into a rogue-like in a way that still manages to feels very tight and streamlined. I think you are really just scratching the surface of what can be done with this mechanic, and I could see it being interesting enough to fill out a larger-scale game (think how cool shops would be). My one opinion is that I think mixing shouldn't take a turn, since it forces players to brew ahead of time rather than react to the perils of the moment.