|Appears in:||Legend of the Guardians: The Owls of Ga'Hoole|
|Acolyte who helped fight the Pure Ones, was attacked and kiled by Allomere with his mate on the night of his son's hatching|
Grettir was once scouting in the Glauxian Brothers Retreat at Perrock, when he felt a disturbance in his gizzard. He quickly flew to a monastery to see what was wrong.
When he arrived, all the monks were slaughtered by hagsfiends. Word soon spread throughout the owl kingdoms of his negligence, forcing Grettir to isolate himself from the owl kingdoms. He settled in one of the owl kingdoms in with his mate, Lygeia. Lygeia eventually laid an egg, whom they both cherished.
A few nights later, on the night of the egg's hatching, the Pure Ones attacked. Grettir and Lygeia paired up to fight the Pure Ones and defend their precious egg.
During the skirmish, Allomere, who was a Guardian close to Grettir, but secretly worked for the Pure Ones, attacked and killed Grettir along with Lygeia and fled before the Guardians arrived and rescued the terrified hatchling, bringing him to the Great Ga'Hoole Tree. The hatchingling was then named Shard and raised to be a Guardian.