Spot
From superman.nu: Supermanica
Spot
The robot dog created by Jor-El as a replacement pet for the baby Kal-El after Krypto is accidentally sent into space.
Exiled to the Phantom Zone by criminals, Spot is later released by Superboy as a playmate for Krypto--whom he saves by colliding with a Kryptonite meteor, destroying his mechanical body in one final heroic act (SB No. 117/2, Dec 1964: "Krypto's Superdog Pal").