Guardian

Guardians are enemies in SS undefined and.

Skyward Sword
In SS undefined, there are two types of Guardians that inhabit Silent Realms. One wields a mace and can run quickly, however, it is limited by obstacles and generally confined to certain areas. The other type is a robed beast that slowly hovers around with two blades, passing through any obstacle in its way. Both types have three distinctive glowing eyes, pure white armor, and robes laced with black and gold. As Link is unarmed while in Silent Realms, Guardians are effectively indestructible.

While Link is in a Silent Realm, he must collect Sacred Tears to successfully complete the trial. Guardians will try to prevent him from accomplishing that goal by chasing him as soon as he leaves the safety of the circle he starts in. If they land a single hit on Link, his spirit will shatter, failing the trial. Link can stop the pursuit by collecting a Sacred Tear, which returns the creatures to their original positions in their inert statue-like state for 90 seconds. A flower above the Spirit Vessel acts as a timer, with its petals disappearing to indicate how long the Silent Realm Guardian will remain inactive. If Link is spotted by a Watcher or touches Waking Water, the effect of the tears will be nullified and the Guardians will reawaken, resuming their search for him.

Breath of the Wild
In, Guardians are ancient machines with an octopus design based on Octoroks. They are powerful enemies, with high health and a laser beam attack that deals six Hearts of damage. When defeated, they drop Ancient Springs and Ancient Screws. Smaller variants of Guardians can be found within Shrines, while deactivated Guardians can be found in various locations around Hyrule.

Trivia

 * Guardians in Skyward Sword are very similar in function to the Phantoms from and.