Other issues:
What are Mark Grayson's powers? What is his origin? Who is he? Where did he come from? This BARGAIN-PRICED zero issue answers all those questions and more. An excellent jumping-on point for new readers, this primer issue brings new readers up to speed while laying down the groundwork for upcoming storylines. It's a MUST-HAVE for current and future readers of INVINCIBLE.
In issue 22, Mark Reveals to Amber that he is Invincible and not cheating on her or a drug dealer. In issue 0; Mark elaborates on his secret life. He explains his origin from start to finish--when he received his powers to when he fought his dad (Omni-Man). Telling Amer the story is still very difficult for Mark but it ends up bring him and Amber closer; which becomes very obvious in the end of the issue.
Note: this issue takes place between Invincible issues 22 and 23.