Belgor
From superman.nu: Supermanica
Belgor
A planet ruled by aggressive tyrants known as the Guardians who value martial conflict and combat skills above all others. Belgor is the home of Ron-Avon, a youth who is forced to challenge Superboy or face the execution of his parents. With Superboy's help, the tyrants are removed from planetary power (SB No. 141, Sep 1967: "No Mercy for a Hero!").