Sal Trapani and Charles Paris take over the art on the Haney story from Metamorpho 7 (July/Aug 66).
Fradon's look for the series is still maintained, which is fairly impressive. Simon Stagg heads off for a convention of vulcanologists, but the entire group winds up getting kidnapped, so Metamorpho, Sapphire Stagg and Java head off to find and save him.
The main reason I am writing about this story is for the unusual reference to Cave Carson. As Metamorpho and the other enter the volcano where the vulcanologists were meeting, they see some writing on the wall, graffiti of the spelunker hero.
Aside from that, this story follows what has become the standard formula for the book, more or less. Metamorpho hunts for Stagg, and finds the one vulcanologist who has not been kidnapped. He is clearly the villain, and Metamorpho suspects that, but still aids him when requested, after a drilling accident opens a hole in the ocean floor.
Metamorpho determines that the villain has placed a neutron dissolver at the Earth's core, to cause all manner of disasters on the surface in a kind of conquer/destroy the world plot. Metamorpho finds and destroys the device, and frees Stagg and the other scientists.