Realms of Arkania: Blade of Destiny

You can only brew poisons if you have the recipes for them, which are scattered throughout the game. You can't actually purchase recipes, so you'll need to find them through dungeons. A good location to check is the crumbling inn (or abandoned hostel), as it's almost guaranteed to have recipes. You can find it by traveling between Daspota and Ottarje.

Once you've searched the dungeon and found a few recipes (you should get at least 3 while you're in there, labeled as aged parchment or something along those lines), you will then need a companion who can read them. This is really difficult, as most starting companions won't have very high stats, and you won't be able to tell what stats you need the highest when you see the documents. An easy way around this is to recruit a mage called Curian. You can find him in Overthorn. Drink in the taverns and he will eventually approach you. Then accept him into your party.

With Curian in your party, he will not only have the skills to read the documents, but he will also have a fairly high alchemy skill as well. So it's wise to have him make the poisons for you. Go into your inventory and read the recipes first. Then click on them again and choose "copy" to add them to your recipe book. Now, you need an alchemy set and some ingredients.

Alchemy set: Most magic-users start with an alchemy set. If you don't have one in your inventory, head to a temple and recruit a witch/druid/magician character, as at least one of these should have a set on them. Then, move it to the person that you want to make the potions. You can also buy a set from an alchemist's shop, but I wouldn't bother if you can get one from a party member.

Ingredients: The ingredients you need will vary based on the poison. You can check what you need by making a camp, using the alchemy skill, and then try to make the poison. it will then tell you what you're still missing, and you can go off to find it. You can either get ingredients by finding them in the wild when making camp, or you can stop by the shops to purchase them. You might also need to stop by a general store, as some items (like bronze flasks) can't be purchased from an alchemist or found in the wilderness.

Finally, once you have what you need, make a camp. Note that, if you just want the achievement and you don't care about the poisons themselves, it would be wise to save your game, as you can just reload and keep using the same ingredients without having to buy more each time.

It's also worth noting that some items are not poisons, but are potions. So be careful what you're creating. I personally used Expurgicum, so I can at least guarantee that this particular poison will work for the achievement.

In camp, choose to use a skill, then select the character that has all of the ingredients and alchemy set. For me, it was Curian. Then, select a recipe to create. Once again, if you haven't read and copied them yet, they won't appear for you. Then, just make the poison, and it will count as progress towards your achievement.

As mentioned earlier, you can do this 10 times, or you can reload your save and create the same poison over and over. Either way, once you've done it 10 times, the achievement will pop!