Click on the ingredients to add them to the cauldron. You can add as many or as few as you like. The order doesn't matter. When you are done click done. That will make the cat drink it. At any time, you can press space to reset. (To many words?) Report any bugs you find.
I looked at the cauldron in potions cave and thought it would be interesting if you could make potions, so I made a game where you did. This didn't take very long. I also wanted to test all the effects.