There was a Superman Family tale where both Superman-One and Superman-Two fought a villain from another dimension who was stronger than EITHER of them together, to save the life of the Earth-Two Jimmy Olsen.
---Al
I was looking for that issue and it was Superman Family No. 187.
I don't have that issue, but would liek to see the merged Superman (Giant Superman?) added to the
https://www.supermanthroughtheages.com/wiki/index.php/Main_Pageinfo:
Story: “A Phoenix of Steel” (8 pages)
Editor: E. Nelson Bridwell
Writer: Gerry Conway
Penciller: Curt Swan
Inker: Jack Abel
Letterer: Ben Oda
Colorist: Anthony Tollin
Feature Character: Superman (last appearance in Superman story in last issue; appears in Jimmy Olsen story in this issue between pg. 8, panels 3 / 4; next appears in Lois Lane story in this issue)
GS: Superman of Earth-Two (next appears in ALL-STAR COMICS #71)
Supporting Characters: Jimmy Olsen (between Jimmy Olsen and Lois Lane stories in this issue), Professor Potter (last appearance in Superman story in last issue)
Villain: Krogg (last appearance)
Comment: This story continues from the Superman story in last issue, crosses over with the Jimmy Olsen story in this issue, and continues in the Lois Lane story in this issue.
Synopsis: In order to stop the monstrous Krogg from devastating Earth-One, the Supermen of both Earths are merged into a single, double-powered Superman.
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