- “I'm gonna need a bag.”— Avery Johnson, after seeing Osmo dead.
Osmo was a Colonial Militia recruit. He was assigned to 1st Platoon, One-Alpha Squad, during the Battle of Harvest near Gladsheim. He was overweight and known to complain and panic. Shortly thereafter, Osmo was transferred to One-Charlie Squad because he yawned excessively and Staff Sergeant Johnson wanted to make a good first impression. He was the first militiaman to be killed in the battle when he was torn apart by an Unggoy named Yull. However, he managed to shoot his MA5, alerting the other militia. This also caused one of Maccabeus' escorts to draw his Spiker and fire a spike into Rol Pedersen's chest, killing him. He was the first UNSC casualty of the Human-Covenant war.
- Halo: Contact Harvest (First appearance)