"A Different World," Part One. The most climactic and earth-shattering story arc in Invincible history starts here! Events in issue 11 changed the status quo of this title forever and this arc will result in even more changes. Reality is not as it was, things are changed, and Mark comes face-to-face with his favorite imaginary hero, Science Dog -- but how is that even possible? Plus: A stand-alone Science Dog back-up story drawn by Invincible co-creator Cory Walker.

Invincible and Rex fight Octoboss and his Squidmen. Rex catches Dupli-Kate cheating on him with the Immortal. Invincible fights Science Dog who turns out to be an alien who took the form of the character. Invincible follows the alien back to their planet and meets....his Dad! The last part of the comic is filled with multiple origin stories by various artists. Origins include: Monster Girl, Immortal, Atom Eve, Rex Splode, Dupli-Kate, and Science Dog.