Form transformation is an ability among guardian spirits that allows them to interchange between a false form and a true form. Unlike transformation into a sprite form, possession of this ability is very rare and the form changed into is different from the sprite ball. A false form is a more normalized and smaller appearance, within the size range of an average human or smaller. For example, Azreal's false form is a two-legged dragon taller than an average human while Huginn and Muninn's false forms are average sized ravens. Alternatively, a guardian spirit's true form is, as the name suggests, is the true appearance of the guardian spirit. Most often, guardian spirits will remain in their false forms while interacting with humans or while trying to remain undetected and will only assume their true forms in order to fight. Guardian spirits in false forms are typically weaker than when in their true forms, although spirits such as Azreal still possess keen skills and strength even in his false form.