What is the name of the final mission in Halo: Reach?

The final mission in Halo: Reach is called Lone Wolf. It follows the last stand of Noble Six on the fallen planet Reach.

Unlike most Halo missions, Lone Wolf is not a conventional objective-based level with a victory state. The player fights Covenant forces for as long as possible, while the deteriorating battlefield and inevitable outcome emphasize the game's themes of sacrifice and loss.

The mission is often confused with The Pillar of Autumn, the preceding level in which Noble Six helps prepare the ship for its escape. Winter Contingency is an early mission, and Noble Actual is the opening cinematic rather than the finale.

Halo: Reach's ending leads directly into the opening premise of Halo: Combat Evolved: the escape of the Pillar of Autumn and its arrival near Installation 04. This connection makes Lone Wolf both a playable epilogue and a bridge to the original game.