It’s issues like this one that make it worth reading all the issues of Marvel Two-in-One.
You may recall that Spider-Man beat the hell out of Sandman and dispersed him in Amazing Spider-Man #218. Well, we learn now that his sand retains sentience and seems to have the ability to draw itself back together.
This forms a nice parallel for the second half of the story, which features Impossible Man’s ability to reproduce through, essentially, mitosis.
In the main story, with Sandman, there’s no fight. Just a conversation in a bar. It’s basically a “history of Sandman” story, and I don’t remember there ever being such a villain-centric issue of a Marvel comic (excepting, of course, Super-Villain Team-Up), let alone a C-lister like Sandman.
A very cool, somewhat experimental and risky issue that might have felt like filler but actually did quite a bit for character development for everyone involved.