FFX-2: Alchemist Achievement
Use Mix 30 times
The Alchemist dressphere is unlocked by completing the "Clean Sweep" mission (see "Tricky Trapper"), and this will allow you to use the Mix command in battle. With that equipped, use Mix 30 times in battle (combine any two items such as simple potions) to unlock the achievement. You can do all 30 in the same battle even if you don't plan to use this dressphere much.