Kingdom Hearts II/Synthesis

Synthesis is the making of equipment from two or more materials. This can be done at any moogle by selecting the "Synthesis" option in the menu. However, moogles have various ranks (from 1-9), and until they increase in level (by synthesizing items), you won't be able to do many of the more advance options, such as creating Mythril Gems. To better farm materials, equip Lucky Rings and the Lucky Lucky ability to the whole party.

While synthesizing, make sure to make upgraded versions of every item from the Free Development and Recipe menus by adding a Serenity material to the original recipe in the Creations menu.