Nothing is known about Osgar's younger years. Skinny and mischievous, Osgar grew up in a family filled with wine-makers. As much as he loved his wine, Osgar always topped off his love for his work, such as stabbing, with a bit of the beverage. Sadistic and oddly whimsical of his work, Osgar built himself an image, which led the Order to find and then induct him into the Zealots. Within the Order, Osgar was entrusted to be a partner in crime for the Order member, The Billhook.
In his rounds, Osgar patrolled the area along the roads of Lincolnscire. It was during one such patrol that he was marked and then fatally incapacitated by the Viking Eivor Varinsdottir, who was allied with the Hidden Ones. Afterwards, Eivor attained a clue from Osgar's personal effects. The clue, mentioning the title, The Billhook, detailed that Eivor needed to search an Aelfgarstun farm northwest of Lincoln in Lincolnscire for more information.
- Like other Zealots, Osgar had unique fighting methods and gadgets in his weaponry. Upon Eivor's instigation, Osgar wielded no shield, attacked using multiple arrows at once, called in for backup soldiers, and whistled for a fellow enemy wolf to fight alongside him.