Hoopa of Malice was, more precisely, the malicious form of Hoopa Unbound. "Hoopa of Malice" was merely Ye Lan's shorthand for that other state, and Hoopa was the only Mythical Pokémon—not a Legendary Pokémon—that Ye Lan referred to with the reverence reserved for a god.
Hoopa had originally been created by Arceus as a unique being meant to balance good and evil in the Pokémon world and maintain stability across its many dimensions and spaces. Much like Marshadow, whom Ho-Oh had created from its own shadow, Hoopa was therefore classified as a Mythical Pokémon.
The difference was that Arceus's "materials" were on an entirely different level from Ho-Oh's. One had used nothing more than its own shadow; the other had combined the power of the Plates, the power of creation, and the energies of good and evil generated by the Pokémon world. The result was the world's only Mythical Pokémon with authority over both "Judgment of Good and Evil" and "Space Transmission," with combat strength that far surpassed even many Legendary Pokémon.
Ye Lan had plenty of complaints about that.
That yellow-haired Arceus got a few Plates and became full of itself. Either it lent them out indiscriminately, only for its avatar to get beaten until it howled when it went to collect them, or it insisted on adding Plate power to everything it made. And look how that had turned out! If Ash and its true form hadn't come to the rescue, Hoopa would have nearly overturned the entire Pokémon world!
That was indeed what had happened. Hoopa had two forms in total. The first was "Hoopa Confined," the form sealed by the Prison Bottle, a legendary item Arceus had forged using the power of the Psychic-, Ghost-, and Dark-type Plates.
In that state, Hoopa was a Psychic- and