As the TMNT phenomenon proliferated to other media, Eastman and Laird found themselves administrating an international merchandising juggernaut. However, this prevented the two creators from participating in the day-to-day work of writing and illustrating a monthly comic book. So, many guest artists were invited to showcase their unique talents in the TMNT universe. The breadth of diversity found in the various short stories gave the series a disjointed, anthology-like feel. Fans stuck with the series, and what was originally intended as a one-shot became a continuing series that lasted for 129 issues, spanning four separate volumes (having 62, 13, 23, and 32 issues in the four distinct volumes).