Rumors indicate Japan will be getting Pokemon X and Y Mega Evolutions for free in an upcoming special event.

According to Product-Reviews, six Pokemon will be available at the event. Gyrados, Scizor, Kangaskhan, Tyranitar, and Mawile will all be given away at level 50 with their accompanying Mega Stone.

The event date will be May 10 through June 22, an each of the weeks will feature a different Pokemon, reported Product-Reviews.

A Diancie event will begin on July 19 in Japan as well, and gamers for the first time will be able to legally obtain the character.
KPopStarz reported that this special game event will coincide with the Pokemon film, 'Diancie & the Cocoon of Destruction.' Those who buy a movie ticket will also receive the legendary Diancie. The event will last until September 30.
In addition X and Y is introducing a legendary Pokemon at a download event, and will be offered for free in Japan.

According to Examiner, players have to first purchase "special advance tickets" for the new animated Diancie movie coming out this summer. The Pokemon available is Darkrai, a dark type as the name suggests.

Darkrai was originally in Pokemon Diamond and Pearl, and had a cameo in Super Smash Bros Brawl for the Wii U.