User blog comment:San&Ashitaka/Character statistics/@comment-3118594-20131028194851/@comment-10733658-20131031154031

There are currently two Guidebooks released by Kodansha. The first, "Inside", focuses on the story up to about chapter 40. The second came out in recent months, and is "Outside". This one has stats for minor characters, as well as information such as Birthdates and many gags that Isayama threw in such as his character interviews (Ghost Marco and Jean, for example) and little sketches of AUs such as Sasha's school band or Eren and Jean as a comedy duo.

It also included some developmental materials for the series, such as Isayama's original concept sketches and layouts. Sasha had short hair, for example, and Marco was a genericly handsome Disney Prince-looking guy, while Bertholdt had a heavy brow like Reiner. We also see how certain scenes and elements changed from the original version, such as Eren originally being aware of his power early on or Reiner declaring his intention to become a Scout.

As was mentioned above, Kodansha USA will be releasing it next year.