Golden Age Flash and co-creating Black Canary, as well as others back in the day, then getting to bring back the Flash to start the Silver Age, co-creating Elongated Man, having the two Flashes meet...
...becoming DC's editorial director, then publisher...
...before moving over to Marvel to work on Spider-Woman, Nova and Star Wars (and others), before coming back to the Flash when Barry Allen got ready to face the Crisis.
Detective Comics #327
....the first of the "new look" Batman (including the yellow oval), Batman and Robin faced a mystery menace with a red X on their foreheads...that allows crook Frank Fenton to paralyze them and escape.
The Elongated Man story (also by Infantino) was reprinted elsewhere.
...where he comes home to find a Fred Dallman in his apartment....a bank vice president who tells Barry that another man will go to prison for a crime Fred committed. Barry works to clear the man, but also discovers Fred died in a car crash....before Barry met him in his apartment!
Infantino also co-created Captain Boomerang!
Adventures Of Rex The Wonder Dog #29
...where Bobo has to disguise himself as a human scientist to catch crook Larry the Lynx at a scientific convention!
Bobo, the Detective Chimp really had little involvement with the rest of the DC Universe until he showed up in Gorilla City during the Crisis On Infinite Earths (having long life as he and Rex found the fountain of youth in a DC Comics Presents back up years before).
Mystery In Space #57
...where Adam and Alanna faced giant aliens called the Rhollians who were affected by a material called Orichalkum, that made them grow to giant size. The aliens try to sink the island, and the island eventually does go underwater after Adam and Alanna gave them chase to let the island sink naturally.
Adam Strange and his adventures on the far away planet of Rann were still only a small part of Mystery In Space at this point, with two other stories in this issue.
Brave and the Bold #45
The DC Special also had a summary of Carmine's career up to that point!