1. Takes place between RGBY and GSC
2. Koga is still gym leader, but will leave after you beat the E4 for the first time. Janine will be able to be battled.
3. Lorlei will leave after you beat the E4 and Agatha will retire. Will and Karen replace them.
4. Your Rival will be Champ in the first round of the E4 and Lance will be in the rematches.
5. You will be able to see how Cinnabar erupted and Blaine moves to Seafoam after the E4.