The add-on with an extra thumbstick on the right will be released in Europe along with Resident Evil: Revelations on January 27th.
The game will be available in a bundle with the Circle Pad Pro, or by itself. Capcom states that Revelations was created from the ground up to fully utilize the 3DS’s capabilities, and players who purchase the Circle Pad Pro as well have the option of even more control setups, including the traditional twin-stick shooter style of gameplay.
No word yet on pricing, but as the Circle Pad Pro was only announced at the Tokyo Game Show in September, this isn’t surprising. Revelations, on the other hand, we know to be set in 2005, as a link in time between Resident Evil 4 and Resident Evil 5.