Template:Infobox Final Smash SSB4 Mega Charizard X (メガリザードンX, Mega Lizardon X), known officially as Mega Evolution, is the Mega Evolution of Charizard in the Pokémon games using a Mega Stone that is exclusive to Pokémon X. It appears in Super Smash Bros. 4 as Charizard's Final Smash. This move is similar to Super Dragon, causing the newly transformed Charizard to constantly fly. Mega Charizard X has two attacks, a physical one where it spins in the direction the Circle Pad is tilted, and a projectile, allowing Charizard to shoot Fire Blasts at opponents.
Description from the 3DS version's foldout
Origin
Mega Evolution is a mechanic introduced in Pokémon X and Y. Only a small amount of Pokémon—including Charizard—can Mega Evolve, and to do so it must hold a special Mega Stone unique to its species. A Pokémon can Mega Evolve in battle, but a trainer can only use one Mega Evolution per battle. The Mega Evolution can change some of the following to the Pokémon itself such as stronger stats (a few Mega Evolutions sometimes decrease stats in favor for others), a different typing, and a different ability. Charizard can Mega Evolve by holding onto a Charizardite X or a Charizardite Y as its item. Charizard is one of two Pokémon (the other being Mewtwo) that have two Mega Evolution forms, the two forms being an "X" form and a "Y" form, with the particular Mega Stone only appearing in Pokémon X and Pokémon Y respectively.
Mega Charizard X specifically induces the most drastic colour change of all Mega Evolutions, turning Charizard from orange to black with blue flames. It also changes type from Fire/Flying to Fire/Dragon, and its Attack, Defense, and Special Attack are all increased. Finally, its Ability changes from Blaze (normal Ability) or Solar Power (Hidden Ability) to Tough Claws, further increasing the power of all direct-contact attacks.
Gallery
Mega Charizard X flying in Super Smash Bros. for Wii U
Close up of Mega Charizard X in Super Smash Bros. for Wii U