- Sandman - Guardian of Dreams
- Toothiana - Guardian of Memories
- Nicholas St. North - Guardian of Wonder
- E. Aster Bunnymund - Guardian of Hope
- Jack Frost - Guardian of Fun
In the books, The Man in the Moon has chosen Ombric, Katherine, and Nightlight alongside North to help fight on the battle against Pitch.
- The term "Big Four" was first used by Jack Frost at the North Pole in the second trailer for the film and later was used by Pitch, when he was confronted by the Guardians in Tooth's Palace in the film itself.
- Jack Frost (The Guardians of Childhood) revealed that Jack Frost was Nightlight, making Jack the first and the last Guardian in the series.
- The Guardians had the ability "to dream-share" - their minds could bond while dreaming.