The Dragon Trio is the three Legendary Pokémon that appear in that have their own games (Pokemon Diamond and Pearl/Pokemon Platinum), and their own movies (The Rise of Darkrai/Giratina and The Sky Warrior/Arceus and the Jewel of Life) Their names are:
Unova Dragon Trio
The Unova trio consits of Zekrom, Reshiram and Kyurem, which are the Yin, Yang, Yaun trio .