Ultraman Saga is a Super Ultraman who is a fusion of Zero, Dyna, and Cosmos, similar to how the latter fuses with Ultraman Justice into Ultraman Legend. His only appearance was in the 2012 film Ultraman Saga.

After Ultraman Zero, Dyna and Cosmos were unable to defeat the apocalyptic Hyper Zetton, Nozomu Taiga, Shin Asuka, and Musashi Haruno were left scattered below the Kaiju. They refused to give up, however, and they kept believing in those Ultramans, giving their Ultra halves a new light and merged into one, thus becoming Ultraman Saga. The hero then continued his battle with Hyper Zetton. They were equally matched, and if the fight had continued any longer, Saga would have lost. Fortunately, with the help of Team U, the Fusion Ultraman managed to defeat Hyper Zetton, destroying him with the Saga Maximum, and the 3 Ultras defused back to normal.

Because of this fusion, Zero obtained the forms Strong-Corona and Luna-Miracle, which would help him out on his later journeys against Belial.