A sage is a master of a particular type of eco, which generally comes with prolonged exposure to eco as one studies it. It appears that over time, contact with eco changes the color of one's skin, as is seen with the skin color of the four sages in The Precursor Legacy. It appears that to be a sage one needs to be capable of channeling eco, ultimately being able to use it in different ways other than channeling normally.
- Samos Hagai, the master of green eco
- The Blue Sage, the master of blue eco
- The Red Sage, the master of red eco
- The Yellow Sage, the master of yellow eco
- Gol Acheron, the master of dark eco.
- Maia Acheron, Gol's sister and also a master of dark eco.
- Tym, a former sage of dark eco.
- Keira Hagai, Samos' daughter and a beginning sage.