Just realized I forgot to post this a few weeks ago :/
Nintendo has announced that as of May 20th 2014 (tomorrow!) the Nintendo Wi-Fi Connection, as used by the Nintendo DS, will no longer be active. This means that all Wi-Fi services from the DS games will no longer work. The online battling, trading and game sync features of these Pokémon games are affected:
- Pokémon Diamond, Pearl & Platinum
- Pokémon HeartGold & SoulSilver
- Pokémon Black & White
- Pokémon Black 2 & White 2
- Pokémon Battle Revolution
- Pokémon Ranger: Shadows of Almia & Guardian Signs
- Pokémon Mystery Dungeon: Explorers of Time, Explorers of Darkness & Explorers of Sky
- Pokémon Conquest
If you have any Pokémon in the GTS you should take them out before tomorrow.
Note that this does not affect trading and battling over local wireless/infrared. Nor does it prevent migration of Pokémon from one generation to another via Pal Park (gen 3-4), Poké Transfer (gen 4-5) or Poké Transporter (gen 5-6).