Power Rangers: Time Team

A new character called the Omega Ranger (any connection to the Space Patrol Delta Ranger of the same title is unexplained) discovers that through unknown means Lord Zedd has reverted to his evil form. Zedd has discovered crystals that allow him to travel through time and form alliances with Ranger-foes of several different eras. The Omega Ranger is confined to the Hall of Legends, the repository of all Power Ranger and non-Power Ranger history, and must enlist the help of other Power Rangers to defeat Zedd and save the universe.