Mega Metagross revealed in CoroCoro

The latest issue of CoroCoro has leaked and confirms that Metagross will gain a Mega Evolution in Omega Ruby and Alpha Sapphire. It will be used by Steven Stone, who was the champion of the Hoenn region in the original games.

Mega Metagross appears to have another Metang fused to it, and from the screenshot below appears to float in the air. It also states that Steven Mega-evolves his Pokemon with a Mega Brooch rather than the Mega Bracelet the player will use in OR/AS (or the Mega Ring as in X/Y).

Mega Metagross is believed to remain Steel/Psychic type, gain the Tough Claws ability, and have a significant increase in speed. We'll bring full confirmation asap.

In-game screenshot of Mega Metagross: