Earth-172 (pre-crisis)

An Earth where Bruce Wayne was adopted by the Kents and became Clark's brother, soon joining him as the crimefighting team of Superboy and Batboy, then later emigrating to Gotham, where Clark Kent becomes employed at the Gotham Gazette. As Batman, Wayne eventually relocates to the Legion of Super-Heroes' 30th century.

Designated canon in Crisis On Infinite Earths: Absolute Edition (November 2005)