The Crimson Sentinels are an elite Spartan fireteam deployed across humanity’s most dangerous battlefronts. Countless victories earned them legendary status... until the Covenant launched a campaign unlike anything humanity had ever faced.

Entire colonies have fallen.

Fleets have been annihilated.

Even veteran Spartans have begun to lose hope.

After suffering devastating losses, the Sentinels retreat to a hidden UNSC facility to search classified archives for anything that might turn the tide. Buried beneath the highest security clearance is a forgotten file...

PROJECT: LEGION

A Spartan so powerful that ONI erased nearly every record of their existence.

The report claims the Spartan accomplished impossible missions alone, defeated overwhelming enemy forces, and disappeared before the Human-Covenant War reached its peak.

Every surviving commander believed the file was nothing more than a myth.

Until the coordinates matched a real location.

Now the Crimson Sentinels have been sent on one final mission...

Recruit the greatest Spartan humanity has ever created.