"Author's Saving Throw".
This entire issue is nothing more than Doctor Strange coming to the prison where SHIELD is holding Doom and talking to him about what's going on in the Astral Plane. Meanwhile, the Maker has come for Doom and SHIELD is desperately trying and failing to stop him. Doom armors up and prepares to fight him together with Strange, and the Maker changes into his true form:
I would be surprised if this was Bendis' plan from the start of this "story", but the Maker was being used in the infinitely preferable 'Ultimates', so he kind of had to. Maybe he had Mephisto on the backburner all this time. Doesn't explain in the slightest why he would pose as the Maker rather than 616 Reed Richards.
This issue is dull, dull, dull. Very nearly nothing happens except pointless talking.
I did not expect Mephisto, I was thinking Morgana La Fay (Especially given that she hates Doom now, and that she has the power to do something like this.). Now, I am interested in this. I will check out the next (Last?) issue.