Oddly, despite the title of the story, Thor is Thor throughout the tale, never changing to Blake once. Anyway, he continues his battle with the Destroyer, not realizing that Sif's lifeforce is powering the creature. Fortunately, Balder's able to get Norn Queen to release Sif in exchange for battling Ulik, and then Thor is brought in for the rest of the battle, winning in the end but losing his hammer to Loki. As for the Destroyer, Odin goes down to Earth and picks him up from the police station. No real reason given for why he'd do that personally, but it does give the amusing spectacle of Odin in a suit for a few panels.
Ulik is a great villain, very much in the "pure savagery" style that Kirby would perfect with Kalibak a few years later. Great to see him and Thor in a knock-down fight.
In the back-up is the final 5-page Inhumans story, "While the City Shrieks", Triton arrives in New York, only to see the city respond with fear and violence. He returns home and convinces Black Bolt that they'll have to move from their island home or risk eventual discovery, hence the mountain location of the "Great Refuge" in then-modern stories.
Colletta inks the 16-page lead story and cover, Sinnott inks the back-up.