Marvel Two-In-One, Vol. 1 #21A (1976)

Black Sun Lives!
Doc Savage and the Thing are both met with female members of the Lightner family, who need help with the males. Time twists four decades together, and father and son merge through technology to become Blacksun, who draws his power from the stars, while also allowing the Thing, Human Torch, Doc Savage, Renny, and Monk to work together to protect the world.
Release Date: 1976