Xotar
Xotar (The Weapons Master, Justice League villain) appears in 3 issues in grailworth's catalog, and was first published in 1960. First appearance: Brave and the Bold #29 (1955), cover dated 1960.
First appearance
Every appearance we value
Action Comics (1938) 1 issue
Brave and the Bold (1955) 1 issue
Justice League of America (1960) 1 issue
Character appearances from the Grand Comics Database, CC BY-SA 4.0.