Mombasa Streets

Mombasa Streets is the first campaign level of Halo 3: ODST, and serves as "the hub", an open-world environment used to access triggerable flashback missions. It is set in the city of New Mombasa.

Summary
Unique as a Halo game level, this level is an open world environment, which contains "beacons", objects left by the Rookie's squad members, which trigger "flashback" levels, explaining previous events. In addition to the beacons, the level will also have additional content, such as Audio Logs.

The city map provided by the Superintendent highlights points of interest, such as the "beacon" objects. The Superintendent will also guide the player into the right direction using the city's plentiful digital signs and billboards.

During the first playthrough, some areas in the city are unaccessible, and the player is forced to play the flashbacks in chronological order. Completing flashbacks unlocks more areas in the city, allowing the player to progress to the next beacon. Once game is completed, the city is fully unlocked for exploration, with also some Mongooses for easier traveling around the city.

Plot
The level starts six hours after the Squad's failed orbital insertion, in the occupied city centre of New Mombasa. Some time after the Rookie wakes up, exits his pod and starts to explore the city, the Superintendent will contact him via a public phone and upload a map of the city to his VISR navigation database.

Intro Cinematic
''{View inside a room in UNSC ship. The Rookie sleeps in the foreground while Mickey, Dutch and Romeo are around a large holo-table, on which a hologram of New Mombasa and the Prophet of Regret's Assault Carrier is displayed.}''

Mickey: The Navy put up a good fight...

Dutch: 'Course they did. It's Earth.

Romeo: Better late than never.

Dutch: How 'bout you show some respect, Romeo?

Romeo: Just saying, Dutch - They missed one.

Dutch: No. They left it for us.

''{Sirens and lights begin to flare. A door into the room opens, and Buck and Dare walk in.}''

Buck: You know the music, time to dance!

Romeo: Hello beautiful...

Buck: Pods. Now.

{The ODSTs grab their gear and start walking to their pods}

Dare: Replacements?

Buck: This many years into the war? Who isn't.

Dare: At least they listen.

Buck: To me. And they're not gonna like what they hear.

Dare: Orders are orders.

{Buck walks to Dare}

Buck: C'mon Veronica! What could be more important than that carrier?

{Dare pokes Buck in the chest}

Dare: My orders. And Buck? Call me Captain. I'll pass on that dance. But you can show me where to sit.

{Dare leaves to the pods}

{Cut to the rest of the team, who are gearing up}

Mickey: What the hell kind of armor was she wearing?

Romeo: Dunno, Mickey. I wasn't looking at her gear.

{Dutch grabs a silenced M7 SMG}

Romeo: Pft! Seriously?

Dutch: Well gonna be close quarters.

{Romeo grabs an M90 shotgun}

Romeo: Exactly.

''{Dutch shoves the shotgun away. Dare and Buck walk into the scene.}

Buck: Second to last. Right next to mine.

Romeo: Cozy...

{Buck walks to the squad}

Romeo: You gonna tell us her name, gunny?

Buck: Miss Naval Intelligence. Your new boss. So check your mouths, find your chairs...

{Buck takes the shotgun from Romeo's hands and angrily shoves him a sniper rifle instead}

Buck:...and get set for a combat drop!

Romeo: What the hell am I supposed to do with this inside a Covenant ship?

''{The Rookie sleeps beside his pod. Romeo walks to him, and hits him with his sniper rifle's butt.}'' {Cut to Rookie's point of view as he wakes up}

The Rookie: Unh!

Romeo: Wake up, buttercup.

{Dutch pushes Romeo away}

Dutch: Relax, Rookie. He don't mean nothin'. Besides, now's one of those times? Pays to be the strong-silent type.

''{Dutch hands an M7S SMG to The Rookie, who attaches it to his pod's weapon rack and sits to the seat. The pod's hatch closes, and the platform all the pods are hanging from descends down into the launch bay}''

{Buck and Dare appear into the pod's viewscreens}

Dare (radio): Latest intel reports Covenant troops are massing beneath the carrier.

{There is a slight flicker of static in the pod's screens as it comes to a stop}

Buck (radio): They’re pulling back? Why?

Dare (radio): We’re not going to find out way up here.

Buck (radio): Troopers! We're green, and very, very mean!

''{The pods rocket away from the ship. Before the Rookie's pod detaches, a countdown sound can be heard.}''

''{As the pod exits the launch bay, a view of Earth low orbit opens before the player's eyes. The tether of the New Mombasa Orbital Elevator can be seen in the background, as well as multiple destroyed UNSC ships. A thick cloud cover down below stretches to the horizon.}''

{The pods pass several destroyed UNSC Frigates during their way down.}

Romeo (radio): I take it back! Navy got its butt kicked.

Buck (radio): Hey Romeo! Remember when I told you to shut your mouth?

Romeo (radio): Yeah…

Buck (radio): Consider that a standing order.

{The pods fall through the cloud layer.}

Buck (radio): Captain! Fifteen klicks off the deck.

{The city of New Mombasa, and the Prophet of Regret's Assault Carrier above it come to view.}

Dare (radio): Stand by to adjust trajectory...on my mark.

Dutch (radio): What did she just say?

Dare (radio): Mark!

Mickey (radio): We’re way off course!

Dare (radio): We’re headed exactly where I need to go.

Mickey (radio): But we’re gonna miss the carrier!

{A stream of energy moves across the carrier.}

Dutch (radio): Radiation!

{A slipspace vortex opens up in front of the Carrier, and rapidly expands}

Mickey (radio): Did the Covenant just set off a nuke?

{The can be seen moving towards the carrier}

Dare (radio): No. the carrier's going to jump! It's a slipspace rupture! You need to-

''{The carrier disappears into the rupture, and pulls the In Amber Clad along with it. A

massive explosion and a shockwave is released as the carrier jumps.}''

Dutch (radio): EMP! Losing power!

Buck (radio): Stabilize, then pop your chutes! We're going in hard!

''{Mickey's pod slams into the Rookie's, cracking the window. Around the pod, and all screens turn red with warnings. The EMP fries the pod's systems and all of the screens go dark.}''

Beacons
There are six beacons around the level, each an object related to a squadmate. The following is a list of the locations of these beacons, and the flashback levels they trigger, in chronological order.

Trivia

 * This level marks the return of the Brute Plasma Rifle.
 * This level is the only level in Halo 3: ODST which does not unlock an achievement upon beating it on Normal or above. This is probably because of the fact that this is a free roaming level.
 * This is the first non-linear open-world level ever in a Halo game, and the largest open environment Bungie has ever created.
 * The level's moody atmosphere, from color palette to lighting and music, is said to be influenced by the Film Noir genre.