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One disappointing limitation of Pokemon Platinum's WiFi play is that the new Platinum formes will simply refuse to work. A Sky Shaymin, for example, will simply revert to being a normal Shaymin when it is brought online. However, there is now a workaround! SCV has discovered an Action Replay code that allows the full use of the new Platinum-exclusive Pokemon formes (Origin Giratina, Sky Shaymin, and all of Rotom's different formes) on WiFi in Platinum.

Discussion Thread

PKM DB Video: (by SCV and fenzo666)