The event will be available over Nintendo Wi-Fi Connection from Saturday 31 July through to Friday 27 August and will allow players, using the Mystery Gift option on the main menu, to collect the Enigma Stone item.

During the game itself, shortly after reaching Kanto, Steven Stone (previously seen in Pokémon Ruby, Sapphire and Emerald Versions) will meet with the player to inform them that a legendary Pokémon has been seen flying around the region. In Pokémon HeartGold, players will be able to fight Latias; in Pokémon SoulSilver, they will fight Latios.

Now, thanks to the Enigma Stone event, the Pokémon not present in each game will now appear. Once players collect the Enigma Stone, they will need to visit Steven Stone in the Pewter City Museum of Science. They will then be given the Soul Dew, which can be given to either Latias or Latios to improve their stats.

Upon leaving the museum, Latios will appear in Pokémon HeartGold Version and Latias will appear in Pokémon SoulSilver Version. They will be Level 40 and, unlike their counterparts in the main game, they will not flee from battle.

The full press release is below.

July 28, 2010 - Pokémon Trainers get ready to unlock the secrets of the Enigma Stone as The Pokémon Company International and Nintendo of America Inc. introduce a limited distribution via the Nintendo Wi-Fi Connection service. Beginning this Saturday, July 31, through Friday, August 27, players of Pokémon HeartGold and Pokémon SoulSilverVersions who have wireless broadband Internet access can receive the Enigma Stone for a chance to catch the amazing, yet elusive, Legendary Pokémon Latias or Latios.

Similar to the other half of the Legendary pair that can be caught normally during gameplay, the Pokémon encountered with the Enigma Stone will be at Level 40. In exchange for the Enigma Stone, Pokémon fans will also get the Soul Dew, a held item that powers up the Special Attack and Special Defense of Latios and Latias. Only Pokémon players who have beaten the Elite Four, claimed the National Pokédex, and have two or fewer Wonder Cards can solve the riddle of the Enigma Stone to capture Latios for Pokémon HeartGold Version or Latias for Pokémon SoulSilver Version.

This special distribution event is only available for a limited time. For more information, players should visit www.pokemon.com.

Latios and Latias are both eligible for use at the Pokémon Video Game World Championships in Kona, Hawaii, August 14-15. Pokémon video game players can still win a spot to compete for the title of Pokémon World Champion by participating in the Last Chance Qualifier tournament taking place on August 13, 2010, at the Hilton Waikoloa Village on the Big Island of Hawaii. For more information on the 2010 Pokémon VGC series, visit www.pokemonvgc.com.