This is for his appearance in fan made games.
Arlon the Serene apears a few times, mainly aiding Pit and Dark Pit, being a master and knowledgable in stealth. In Chapter 8, helps Pit and Dark Pit by locating where Precipitous hid and then uses his "Power of Invisibility", as Palutena calls it, though he prefers the term "Stealth Covering." Although nearby enemies can see Pit and Dark Pit's glowing wings when "invisible", Precipitous is kept from knowing of their presence, helping Pit and Dark Pit reach him. After the battle with Precipitous, he attempts to escape again, but Arlon shows up blasting him with a powerful laser.