ONI Alpha Site
This article is about the campaign level. For other uses, see Alpha Site (disambiguation).
This is the first and only level in the game in which the player encounters groups of suicidal Grunts using any skulls. This is also the last level the player is aided by normal Marines.
The level opens as Dutch and Mickey are setting demolition charges to destroy the bridge leading to the complex to prevent the Covenant forces from accessing it. After the charges are armed, an NMPD officer commands the Superintendent to unlock a keypad on a bridge toll booth so they can remotely detonate the charges. The AI is hesitant at first, but eventually lets Dutch destroy the bridge. After this, they fall back deeper into the facility, fighting off more waves of Covenant until they are forced to retreat into the ONI building itself. Dutch and the NMPD officers fight off the squads of Brutes, Grunts and Jackals that continue to push into the building. Eventually the fight is brought up to the roof of the facility, where the final Covenant infiltrators are killed. A Pelican picks up Dutch and Mickey, and the level ends as Mickey remote detonates the charges in the ONI facility, destroying it.
ONI Alpha Site
2 hours after drop
The Wraith starts to open fire.
Mickey finishes arming the detonator.
Dutch looks down the bridge to a watchtower with an NMPD Officer in it, which almost gets hit by a plasma mortar.
The two run down the bridge, while another Wraith moves in and starts to fire.
The view switches to Dutch, who takes cover behind a destroyed Warthog, while Mickey hides behind a barricade. Plasma shots from the Wraiths secondary gunners streak past them. A plasma mortar lands several metres in front of Dutch, staggering him.
Dutch looks back at the Wraiths starting to move up to the bridge. Their gunners continue firing at him.
A squad of Marines on the bridge buckle under the Covenant assault, and are forced to pull back.
If the player turns to fight the advancing Covenant horde:
If the player walks past the first charge:
If the player walks past the second charge:
After the second charge is armed, two Banshees join the fight.
If the player doesn't go up the ladder to the tower
Dutch heads for the tower and goes up the ladder.
The Superintendent gives off a chime.
If the player doesn't trigger the charges yet:
If the player further stalls:
If some Covenant succeed in crossing the bridge:
Dutch or the NMPD Officer triggers the charges:
The bridge is destroyed, killing all Covenant troops still on the bridge.
Mickey, Dutch, the Marines and the NMPD Officer make their way under the wall.
If the player doesn't go under the wall:
If the player still doesn't follow Mickey:
The group make their way up the stairs, to the courtyard.
Mickey and Dutch make their way up the hill, where a group of Covenant infantry, including a Mgalekgolo pair assault more NMPD Officers and Marines.
Soon, more and more waves of Covenant are dropped off. Multiple Wraith tanks are dropped in by Phantoms.
The human forces fall back to the entrance to the ONI building. They fend off increasing numbers of Covenant.
A mass of Covenant soldiers, including a Jiralhanae Chieftain charge the human defences. The ODSTs retreat into the building's interior. NMPD Officers go outside in a last effort to hold back the Covenant. Dutch and Mickey go to a group of officers in the center of the complex.
Cutting noises and sparks appear on the sealed doorways.
The doors explode. Jiralhanae can be heard giving out battle cries.
After many waves of suicide Unggoy, Kig-Yar and Jiralhanae join the battle. Eventually, the humans staunch the forces coming in from the doors, however the Covenant start dropping in troops behind Dutch and Mickey.
Soon the Covenant reinforcements are defeated.
An NMPD Officer arrives with an elevator.
Mickey and Dutch, along with any survivors from the previous battle, get in the elevator.
Dutch activates the elevator, and they slowly make their way up.
With IWHBYD skull activated:
On the way up they are ambushed by a swarm of Yanme'e.
They soon defeat the Yanme'e and make it to the roof, where a Phantom is dropping off a pack of Jiralhanae Jumpers, along with Kig-Yar and Unggoy infantry.
On Legendary, a Jiralhanae Chieftain will be present.
If the player doesn't board it:
If the player still doesn't board it:
If the player still doesn't board the Pelican:
or, with IWHBYD skull activated:
As soon as the player boards the Pelican, the level ends.
Mickey and Dutch board the Pelican, remove their helmets and take a seat. The NMPD officer on board looks at them.
The Pelican lifts off and departs the ONI building
Mickey nudges Dutch.
Mickey points to the ONI Building, and starts to count down from three on his fingers. When he reaches zero, he detonates the charges, destroying the building.
The Pelican flies away as the view changes to a Superintendent camera, the avatar gives a confused then angry face as the building is destroyed.
The cutscene ends. Screen fades to black.