Can I link my US and EU Battle.Net accounts together?

Yes, RaiderIO now supports linking all regions associated with a single Battle.Net account together into one RaiderIO account.

To do this:

1. Visit the Blizzard Account page on RaiderIO: https://raider.io/settings/battlenet
2. If your Blizzard Account is currently synced, click the red "Disconnect Blizzard Account" button at the bottom of the page
3. Look for the list of multiple regions and click however many you have characters on that you want to claim
4. Click "Link Blizzard Account"

And that's it! A few seconds later you should see all of your qualifying characters showing up in your characters list.