NOTE: Post Updated February 2019
I love these two issues. The villain is Basilisk and the story is perfectly adequate. That’s not why I love them. It’s because Marvel enmeshed a done-in-one format completely in continuity–not just in its own title, but it crosses over into the other done-in-one showcase book, and both tie into the overall Marvel continuity.
In the first four pages, there are five references to other issues and storylines. Marvel Two-In-One #17 starts with Spider-Man arriving back from his time-travel engagement in recent issues of Marvel Team Up. Then it jumps back to Thing, who is still finishing up with Ka-Zar from last issue of MTIO. By the time the two titular heroes hook up, the issue is almost over, so it’s continued back in MTU.
Creators: Bill Mantlo and Sal Buscema (MTU), Ron Wilson (MTIO)