Global Terminal
The Global Trade Station, GTS for short, is the worldwide network over which players of Pokémon Diamond and Pearl can trade Pokémon via the Nintendo Wi-Fi Connection. It is located in Jubilife City. In order to access the GTS, the player must have the Coal Badge.
Inside, there is a large globe, called Geonet, on which players can indicate their location, and on which small dots representing players they have traded with will appear.
If the player talks with the woman at the counter, she will direct him or her into a room in which they can either put up a Pokémon to be traded or trade a Pokémon they own for one that has been put up for trade.
Pokémon searches, after being confined to one species that has been seen by the player, can be further narrowed down to level and gender of the Pokémon available. By level, players can search for and request Pokémon level 9 and under, level 10 and up, level 20 and up, and so on to level 100, or they can search for Pokémon of any level. Gender is similar, with the player being able to search for male, female, or either gender of the selected Pokémon.
Pokémon offerings are similarly governed, as the requested Pokémon in return cannot be any Pokémon that the player has not seen. Unfortunately, Pokémon that are offered cannot be bargained, as the player has to choose one Pokémon he or she wants for it, instead of having a more flexible list.
Like normal, inter-game trades have been since Generation II, a Pokémon can also hold an item when being offered or traded. This may add incentive for a player to trade his or her Pokémon for a Pokémon that they already own, instead of just trading to complete the Pokédex, in order to get the item attached. Just the same, Pokémon that evolve after a trade will do so.
Controversy and criticism
Although being a well-meaning trade function, the GTS has come under much criticism from many players. Many traders ask for a version-exclusive legendary in exchange for a ridiculous offer, and many Pokémon asked for are at levels that are impossible for that Pokémon to be at, such as a level 9 and under Dialga. Other trades are dominated by demands of Pokémon currently being featured in Pokémon marketing, such as Munchlax or Lucario. Finally, the inability to ask for a Pokémon the player has not seen makes it impossible to trade for event Pokémon such as Manaphy and Pokémon that can only be found in Generation III games over the GTS without having seen the Pokémon through a cheating device. Nintendo has not commented on these pitfalls.
There is also a risk of getting hacked Pokémon when trading for legendary Pokémon and rare Pokémon since the GTS does not include the OT or the ID No. when seeking Pokémon.
A third problem is that a Pokémon with a Classic Ribbon can't be traded, making event Pokémon even more difficult to obtain.
Legendary Pokémon ban?
On July 3, 2007, legendary Pokémon became banned from being traded on the GTS. A similar incident occurred in Pokémon Battle Revolution on the same date.
The banning received a large amount of controversy. Nintendo stated that it was a "technical difficulty", which proved true when legendary Pokémon were again allowed to be traded over the GTS and battled in Battle Revolution.
Trade evolution glitch
There is a glitch with the GTS that allows Pokémon to evolve by being traded, but without actually trading them. Players must first place a Pokémon that evolves by trading it (with the correct held item, like Metal Coat for Scyther or Electirizer for Electabuzz) onto the GTS. For security reasons in case the Pokémon is taken, it is recommended that a player request an impossible trade, such as a level 9 Mewtwo.
The player must then search for a Pokémon on the GTS and trade for it. After this has been done, returning to the Pokémon that was placed on the GTS by the player and taking it back will cause it to evolve. Players, of course, must be careful with this, as the Pokémon can, in fact, be traded, if the trade is not unreasonable enough, and it may be difficult to find a reasonable trade on the GTS itself.
GTS morphing glitch
There have been a few reports of a new glitch happening in the GTS that causes a player's offered Pokémon to become glitchy. The Pokémon's sprite will morph into a different Pokémon (the most common report is Azumarill), and the gender might be swapped as well. It will also say it is the same species it used to be (example: A morphed Heatran would still be Heatran/Heatran) and will be holding a Seal Bag (glitch item). There is no confirmed way to deliberately access this glitch; however in many of the reports, people have reported that the glitch happened right after the GTS came up with no searches for any of the Pokémon, but did not send out a Communication Error. After it stops blocking all access to other Pokémon, it is believed that is when the glitch is most likely to happen. Trying to withdraw the glitch Pokémon will result in a Communication Error but is believed that if the game lets a player withdraw the new glitch, that the player's game will malfunction.
"Arceus's vanishing glitch"
There have also been a couple of instances of a "vanishing" glitch on the GTS. After uploading a pokémon to the server and searching around for a trade, the "summary" button is replaced with "deposit", suggesting that the pokémon has been traded. Selecting "Deposit" will cause a communication error, and the player will return to the front desk. Logging on to the server again will cause the pokémon to reappear, with no noticable changes.
Incidentally, both occurances involved the legendary pokémon Arceus. In one instance, the offered pokémon was an Arceus; in the other instance, the pokémon wanted was an Arceus.