Perhaps taking a similar approach to Groudon and Kyogre from generation three, two of the newest legendary Pokémon in "Pokémon Sun" and Pokémon Moon" will encounter new forms.

It's All About Phases

According to The Pokémon Company International, Lunala, the mascot for "Pokémon Moon," and Solgaleo, the mascot for "Pokémon Sun," will have new forms. Not too much information has been revealed, such as how the forms occur -- will it be due to weather condition, a stone or battle features?

It is confirmed that Solgaleo and Lunala will change appearances when "releasing their might powers" into Radiant Sun phase and Full Moon phase, respectively.

Based on the official art of the legendary Pokémon, Lunala and Solgaleo appear brighter or more transparent.

Don't Forget Magearna

Meanwhile, there is a third special Pokémon in the game that has long been confirmed before Solgaleo and Lunala. Magearna will be Mythical Pokémon in the new Nintendo 3DS games. The Mythical Pokémon, a dual fairy and steel-type, was created by a scientist 500 years ago and within the center of its chest is the Soul-Heart, which is said to be "an artificial life which was created using the life energy of other Pokémon."

Magearna has the ability Soul-Heart, also new to the games, and it raises Magearna's Special Attack by one each time another Pokémon in the arena faints.

"Pokémon Sun" and "Pokémon Moon" will be available for the Nintendo 3DS on Nov. 18.