This is the first official adaptation of Dungeon Crawl Classics to another genre, specifically post-Apocalyptic fiction, and as such it has been widely covered elsewhere. Indeed, the Glowburn podcast is about Mutant Crawl Classics (and related games), and has two episodes at the time of this writing which are dedicated to taking a first look at the rules. You can listen to them here and here.
Episode 43 of Spellburn was likewise about Mutant Crawl Classics. Mutant Crawl Classics has also come up from time to time on the Sanctum Secorum podcast, and especially on Episode 15 (Kamandi: The Last Boy on Earth).
As of this writing, the game has not yet been released into the wild, but backers of the Mutant Crawl Classics kickstarter have had a chance to delve into the book. Reviews of Mutant Crawl Classics can be found here, here, here, and here. There is an extensive review in Meanderings #2.
I was lucky enough to do some playtesting of MCC #3: Incursion of the Ultradimension by Michael Curtis, and therefore had some early access to the rules. Interestingly, the plantient (sentient and mobile mutated plant) that was one of the pregenerated characters was instantly named Yew-root (after Groot) because of his mutations. We were all a little sad to realize that raccoons were not listed among the baseline of manimals (mutant animals). That's easy enough to fix!
Both Dungeon Crawl Classics and Mutant Crawl Classics allow for gonzo action, but Dungeon Crawl Classics seems more heroic to me, whereas Mutant Crawl Classics is tinged with survival horror. Certainly, the classes available to Pure Strain Humans seem weaker than the core classes in Dungeon Crawl Classics; the game relies upon interaction with artifacts and AIs as part of its balance mechanism.
One of the neatest rules in Mutant Crawl Classics may actually cause the most difficulty in actual play. Your mutant (or plantient, or manimal) has a fluctuating genetic sequence, meaning that you may gain or lose mutations over the course of play. When I sit down to play Dungeon Crawl Classics, I can use the Purple Sorcerer tools to create customized spellbooks, and can use The Crawler's Companion to roll spell results if I failed to plan ahead. These things, along with the Ready Reference Book, mean that I don't have to actually carry the core rulebook around with me. (I usually do; but I don't have to.)
When creating pregenerated characters, I will print out specific spells so that the players need not flip through the book. Again, Purple Sorcerer makes this easy. When I ran my first playtest, I did the same for mutations.
And then the mutations changed. Not just once during the session, either.
There will be reason, therefore, to make something like the Ready Reference Book for Mutant Crawl Classics. There is also good cause to create a Sorcerer's Grimoire-type tool for mutations, and an ap that can roll mutations you didn't realize you'd need (and therefore did not print out) before you sat down to play.
The artwork is, by the way, glorious.
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