Vaarna_Aarne
Notorious Internet Vandal
Alchemy is leveled by doing Experiment assignments, which generally require certain types of potions. Healing potions you can obviously just buy, but generally you either need a lot of time to refine materials if you don't have a large number of slots. You will also eventually start needing Aqua Vitae (and later on refined forms of it) as an ingredient for potions AND the experiment, so you're generally stuck needing lots of vitriol. Good news is that Alchemy is pretty much guaranteed to progress at least 1 rank per day if you babysit it a little.