After the fall of Project Freelancer, Oregon joined up with Nevada to form the Splinters, due to being abandoned a long way from home after many years of training to become an agent. However, things spun out of control and Oregon defected from the group with Hawaii, who sacrificed herself to save him. He ended up severely wounded in Blood Gulch, where he made a slow recovery, convincing himself that Hawaii was out there and still alive.
Oregon rallied the troops in Blood Gulch and fought off Command's backup, then sought to kill of the Splinters slowly but surely. Eventually it came time for him to take a chance and break into Fenton with the hopes of Hawaii being alive and kept prisoner there. When he and Fireteam Delta discovered he was right and also rescued Campbell, they made it back to the canyon safely. Once Hawaii and Oregon caught up, they uncovered their love for each other which had been lying underneath the surface their entire relationship.
Oregon led Fireteam Echo on a mission to destroy the Child of Necessity and finally kill Nevada, but only the former objective was a success. He felt extreme guilt for losing one of the soldiers in the explosion of the ship and letting the boss go, but just a week later Nevada came to kill Oregon and Hawaii himself. Oregon called for backup and a group of sim troopers defeated Nevada, finally ending the Splinters. Oregon then briefly went dark with Hawaii after nearly losing her in the fight.