WWE '13 on the Nintendo Wii requires players to complete Match and Historic Objectives in the Attitude Era mode to unlock characters, arenas, and championships. Save data is stored on the console's internal memory, and unlike other platforms, this version requires manual progression rather than a cheat code for unlocking content. For detailed lists of every unlockable item and the specific match requirements, you can refer to the comprehensive WWE '13 Cheats and Secrets guide on GameFAQs

Arenas: Classic venues such as Bad Blood ’97, SummerSlam ’98, and WrestleMania XV.

I couldn’t find a specific “report” or official document regarding WWE ’13 save data on the Wii. However, here’s a concise technical summary based on known issues and community findings:

1. Data Corruption: Save data can become corrupted due to various reasons, such as sudden power outages or hardware failures.
2. Save Data Loss: Save data can be lost if the Wii's internal memory or SD card is damaged or formatted.
3. Incompatibility: Save data may not be compatible with different versions of the game or Wii console.

Save Data Management

Select Data Management, then Save Data, and finally the Wii tab.