Dive into the gripping universe of "Invincible" with issue #21, boasting a 9.6 Near Mint+ grade from the Professional Sports Authenticator (PSA). Published by Image Comics in 2005, this single issue comic book features the first appearance of Darkwing II, a key character that fans and collectors alike will want to cherish within their curated collections.

Credited to the artistic talent of Ryan Ottley and the storytelling prowess of Robert Kirkman, this Modern Age era superhero gem is a testament to the rich tradition of US Comics. As a part of the "Invincible" series, issue #21 is a must-have for enthusiasts of the genre, ensuring its place as a revered piece of comic book history.