Common skills are special skills in Mana Khemia: Alchemists of Al-Revis and Mana Khemia 2: Fall of Alchemy that can be equipped to any of the characters in the game. You can get them by using Co-op Synthesis and Each common skill can only be unlocked from certain E-Effects of an item. In order for you to use these skills, you need to embed them onto your equipments by using the Althanor for Synthesis.