Celestials
The Celestials were one of two twin civilizations of Latios and Latias, the other being the Moon Tribe. The Celestials lived on a floating island that hovered around the world, and were guarded by the Ho-Oh Shiranui. However, when Orochi and Yami learned the Lunar Pendant was among them, they worked in tandem to assault the Celestials. Orochi slaughtered a good portion of them before doing battle with Shiranui, and when the rest tried to flee in the Ark of Yamato ferried there by the already-destroyed Moon Tribe, but Yami and many Demon Mutagen-altered Drapion were waiting inside and slaughtered them as well. Currently Waka (who had the Lunar Pendant in the first place) is the only known survivor, though Orochi hinted at knowing of one other.