Since the original Persona 3, Kohyru has served as the ultimate form of the Hierophant Arcana, and this stays true in Persona 3 Reload. You'll need a certain key item in order to create Kohryu in the Velvet Room. On top of this, you will also need four Personas registered in the compendium before the Special Fusion becomes available. Kohryu is a great Persona to have on your team in Persona 3 Reload, but if you want, you have the option of making it even stronger by using Skill Cards.