A Guardian is a mysterious entity existing within the world of Tails Gets Trolled. At the current point in the comic, only three are known, those being Dusk Hunter (controlled by Demaro), Coyote's guardian, and Miladox.
There is not a lot of information regarding how the Guardians came to be or how they obtained their names as "Guardians". The tribe responsible for teaching Troll King the Words of Death are said to be knowledgeable seeing as they passed some knowledge regarding the Guardians onto him.
In the main story, two Guardians are seen in action. One of Dusk Hunter, under the control of Demaro. It resembles a bull and fights primarily by charging at its foes, and causes the sky to become red when it battles. The other is Coyote's unnamed Guardian, resembling a large tree. It turns the sky green during battle and appears to be more powerful than Dusk Hunter seeing as it changed the sky from red to green when summoned. Its exact abilities are unknown because Coyote recalls it immediately after sending it out.
At the conclusion of Coyote's battle with Miladox, he realizes that Miladox must be a Guardian just like Dusk Hunter and his own tree like guardian. He then takes Miladox and removes him from inside Demaro's dimension, and places him within his book. At the current point in the story, Coyote owns all known Guardians.
The Guardians are said to be neither alive or dead by Demaro, though what this implies is currently unknown. Troll King later reveals more details regarding their nature during Chapter 17: Psychological Assessment. He reveals that the Guardians are capable of changing the color of the sky when they battle, visible to anyone within a 100 mile radius of them. They are also said to battle each other in "random events" from time to time. When two Guardians do battle, the stronger of the two will change the sky to its color.
List of known Guardians