Legendary Mortality Trio: Xerneas, Yveltal, Zygarde

The sixth generation of Pokemon released the smallest number of Pokemon in any generation, and this shows greatly in the number of Legendary and Mythical Pokemon. There is literally only two trios apart of this generation, and the Mythical Trio isn't even considered to be a real trio by many.

Anyways, the first trio is the Legendary Mortality Trio of Xerneas, Yveltal and Zygarde, and it has one of the greatest backstories known to Pokemon. The trio is widely considered to based on Norse Mythology.

As for the Norse Mythology, there is a place known as Yggdrasil that is basically a tree that represents life and the ecosystem. Yveltal is like the Eagle in the Tree, Xerneas is the Dear, and Zygarde is the Serpent. Xerneas represents life, Yveltal represents destruction, and Zygarde represents recovery.

This theory makes quite a bit of sense, considering the story of these three in the Pokemon Games. Apparently, there was once a King known as AZ. There was a great war going on at the time, and he created a machine that would ultimately end the war. This machine destroyed everything, and Yveltal was the main power source. Xerneas was able to share and restore life, and Zygarde is believed to have restored the ecosystem after the Ultimate Weapon was used.

All three Pokemon possess powers that give them the right to be called the Mortality Trio. Xerneas and Yveltal basically share the same stats, each with an exclusive move. Yveltal has the move Oblivion Wing that allows it to restore Hit Points, while Xerneas has the move Geomancy that allows it to double its Special Attack, Special Defense, and Speed in two turns. Zygarde in its regular form doesn't stack up to the two, but in its perfect form shown above, Cell, err um, Zygarde has more than enough power and moves to take out the other two.

#716 - Xerneas: Xerneas can only be found at the end of the main storyline in the game it's the cover face for (Pokemon X), in Team Flare's Lab.

#717 - Yveltal: The exact same thing can be said for Yveltal, but for Pokemon Y.

#718 - Zygarde: Zygarde can be found in both Games after the main storyline in Terminus Cave.