Mega Evolution, Pokémon Wiki

Mega Evolution (メガ進化(しんか), Mega Shinka) is a concept introduced in Generation VI. It consists of certain Pokémon gaining an ultimate form of themselves. The Pokémon need special Mega Stones in order to evolve into their final form for one-evolution/branch evolution families and ultimate forms for two-evolution families. Also, Pokémon can only gain their ultimate form by using a Mega Stone unique to their species. For example, to Mega Evolve Blaziken, Blaziken must be holding the Mega Stone, Blaz

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Mega Sceptile

Rayquaza (Mega Evolution Special), Pokémon Wiki

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Top 5 Mega Evolution Pokemon of all time

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