Diffusion is a Merit ability for Blue Mages level 75 in Final Fantasy XI. It allows a Blue Magic enhancing spell to affect all party members in range. The area of fffect is centered around the user and affects only enhancing blue magic spells and may only be applied to the user. Spells cast after Diffusion also affect the user's Adventuring Fellow, but not other party member's fellows. It lasts for either 1 min or until the next enhancing blue magic spell is cast. It has a recast time of 20 minutes (-2 minutes and 30 seconds for every additional merit). Fully merited, the minimum recast of Diffusion is 10 minutes.