Niffelheim

You must use 10 unique Potions, it can’t be the same Potion 10 times. The good news is that you'll most likely get this a naturally as you progress through the story.

The main 3 Potions (Health, Strength and Defense) all have 3 tiers to them. You'll start off using the Weak Potions, then the Strong Potions and finally the Thick Potions (the higher quality potions require you to update your Alchemy Station). If you use 1 of each tier, that’ll be 9 right there.

Along with Potions, the Brews also count towards this trophy and you should absolutely be using those when you go up against the Bosses. There are 4 available (Hunter, Troll, Spider, Deadman) and each have 2 tiers (weak and strong) so there's an additional 8 you can easily knock out.

One of the most important Potions, however, will be the Potion of Regeneration. While this is used as an ingredient in better quality Potions and Brews, it is also the only item that will remove Mortal Wound, the debuff you receive when you die. The debuff can stack up to 5 times and each time will greatly decrease your character stats (as well as take 20% of your Gold). While you'll actively be working on not dying as you play, chances are it’ll happen once or twice so be sure to have a few Potions of Regeneration available for when you need them.

All in all, drinking 10 unique potions won’t be overly difficult. Once you've drank the 10th one, the trophy will unlock.