Brave and the Bold (1955 1st Series DC) #29
Published May 1960 by DC.

Second appearance of the Justice League of America in "Challenge of the Weapons Master!"
Script by Gardner Fox
Pencils by Mike Sekowsky, inks by Bernard Sachs and Joe Giella
Having found an ancient book that appears to indicate that he once defeated the JLA, Xotar travels from 11,960 to the present to test four weapons against the Justice League, in order to determine which weapon will help him defeat the Intersolar Police of his own day; But the JLA counters each of Xotar's weapons and returns him to face justice in his own time.

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