Swifty

The intelligent greyhound, adopted as a friend for Krypto, who occasionally is endowed with temporary super-powers by Superboy.

Superboy first meets Swifty in June 1963 when he saves the dog from the murderous foxhunter who is the dog's owner. The grateful hound tracks down Superboy in the latter's Clark Kent identity, trailing him "over hundreds of miles." Inspired, Superboy gives Swifty a serum similar to the one developed by Roz-Em to give Jonathan & Martha Kent super-powers. Equipped with a "spare cape," Swifty is trained to protect Krypto --who unfortunately assumes the new dog is his replacement and storms off. However, when Swifty's powers wear off, Krypto has a heroic change of heart and saves his rival from drowning, finally learning that Superboy intends for Swifty to be "a fitting playmate to romp through space with ... a canine pal who could save [Krypto] from Green Kryptonite!" (SB No. 105: "The Superdog that was Greater than Krypto!").