Xerneas does not have a Mega Evolution.
mega drain in Pokemon is a grass type move that works better leech seed or leech life
Mewtwo can Mega Evolve into either Mega Mewtwo Y or Mega Mewtwo X.
The listed Pokemon can evolve in X and Y: Mewtwo, Blaziken, Lucario, Venusaur, Charizard, Blastoise, Alakazam, Gengar, Kangaskhan, Pinsir, Gyarados, Aerodactyl, Heracross, Ampharos, Scizor, Houndoom, Tyranitar, Gardevoir, Mawile, Aggron, Medicham, Manetric, Banette, Absol, Garchomp, and Abomasnow. These Pokemon can mega evolve only in Omega Ruby and Alpha Sapphire: Beedrill, Pidgeot, Slowbro, Steelix, Sceptile, Swampert, Sableye, Sharpedo, Camerupt, Altaria, Glalie, Salamence, Metagross, Latias, Latios, Rayquaza, Lopunny, Gallade, Audino, and Diancie.
Beat the 5th Gym, and go east of Mauville, then surf east. Go on the adventure with Steven on Route 118, then he will give you the Mega-Whatever that allows you to mega-evolve. Then simply attach the mega stone of whatever you're trying to mega-evolve, and have fun!
You have to come to the place where you caught Groudon/Kyogre, but you have to take both Groudon as Kyogre with you.
its magma stone and its in stark mountain after you beat the game
be super mega fat
To beat May, the best thing to get is a Roselia and train it really high. It learns Mega Drain @ lv.17
Yes, the Mega Gyrarados is a flying Pokemon and a water Pokemon.
Xerneas does not have a Mega Evolution.
Mega Rayquaza
The new Mega Evolutions that premiere in Pokémon Omega Ruby and Pokémon Alpha Sapphire are Swampert, Sceptile, Latias, Latios, Rayquaza, Diancie, Beedrill, Pidgeot, Slowbro, Steelix, Sableye, Mawile, Sharpedo, Camerupt, Altaria, Glalie, Salamence, Metagross, Lopunny, Gallade and Audino which officially adds up to a total of 46 species being capable of Mega Evolution and there are 48 Mega Evolutions overall as of Pokémon Omega Ruby and Alpha Sapphire's release.
Yes, you can find a Snorunt at Shoal Cave during low tide and evolve it, and find the Glalieite in the Shoal Cave basement.
No, because Mega Evolution wasn't introduced until Pokemon X and Y.
My good sir, mega balls are nonexistent in the pokemon video game series.
Have it hold the Sceptilite, then press "Mega Evolution" during a battle to Mega Evolve it.