For the Boiling Mine: Taste of Steel event, a nice addition for it could be an event shop with its own unique currency that can also be used to brew powerful version of existing potions, that being a new Pickup Resource called "Silver". Silver can be dropped by enemies via "Liberation", specifically by defeating Whip Controllers, Dominotaurs, and Mine Walkers. It will function as a means to trade in a shop or can be used in the cauldron.
Silver only = "Strong Arm": +45 base damage
Silver + Bronze = "Hellstorm": 1k instant damage
Silver + Wood = "Manic": +30 Attack Speed
Silver + Tar = "Bloodthirsty": Heal = Damage dealt × 8
Silver + Stone = "High Roller": +100% Critical Chance, Critical Multiplier changes every frame from +1.1x - +3x, with the probability being higher around +2.1x