The Battle CD is a side quest in XD activated upon receiving the CD Case from the lady at the front gates of Phenac on your first arrival there. The lady will prompt you to visit Realgam before you will let you enter Phenac, and you can find the corner for Battle CD in the right room of the Realgam Tower’s lobby.

The Battle CD makes use of virtual battles, and has different sets of rules or limitations on each CD, pretty much like Earl’s Training School back in Stadium 2. The difficulty is denoted by the number of stars, and goes up as the number progresses. There are a total of 50 CDs, and they are scattered throughout Orre. Once you’ve found a CD, you can challenge it at the Battle CD Corner in Realgam. You can challenge it over and over again should you fail, and advice will be given after your first defeat.
On the first clearing of each CD, you will be rewarded with special items such as revives, ultraballs, or even the sacred ash. Once you’ve cleared all 50 CDs, you will receive 15,000 pokecoupons. The following lists the location and content of each CD, with strategies on how to clear them:

 
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