The Fullmetal Alchemist franchise
is heavily based upon Alchemy. They use things such as transmutations circles, and laws of alchemy (such as equivalent exchange). Alchemy is used in many ways, such as creating metals, reshaping objects, fixing things, creating fire, creating water, and removing matter. The power Alchemy holds in the franchise is mighty, though with the rise of Alchemy, science tends to be left hanging to dry. It has taken a backseat in this world, and is very unpopular. Though the first rule of Alchemy is equivalent exchange.
The Atelier Iris
series features alchemy as one of its central game play features. Characters can create items of all sorts using alchemy, including food, armor, weapons, medicine, and explosives. Most of the best equipment in the game cannot be bought, and must instead be synthesized. In Atelier Iris 1
alchemy is accomplished by breaking down physical objects and items into their basic elemental energies and then using this energy, along with the help of elemental spirits, to form new items.
Synthesis can also be performed by directly combining items based on recipes to make new items, without breaking down the initial ingredients to basic elements. Ingredients may be substituted to discover new recipes.
Many games use alchemy as a way of item creation. Many times a workbench or similar area is used by the player, who gathers the necessary resources and creates items. One game that uses this is Neverwinter Nights.