Firefight

"Drop feet first into a new way to play Halo with the cooperative campaign mode, Firefight."

- Bungie

Firefight is a single or cooperative campaign mode for Halo 3: ODST where up to four players can participate with one another via System Link or Xbox LIVE and combat against the Covenant. The mode allows four teammates to battle in multiple environments, on foot or in vehicles, and against increasingly difficult waves of Covenant attackers.

Gameplay
Firefight will have no limit on the waves of enemies and will continue until the squad has completely run out of lives, however there are five waves in a Round and three rounds in a Set. The Set, Round, and Wave the player is in can be seen at the top left of the screen, with the number of players lives being 7 to share between all of you when Firefight is first started. The Set number is represented by a number from one to infinity, the Round will be represented by a circle, going from left to right with the wave the player is in shown under the Round.

At the end of a round there will be a brief pause where the player will be allowed to recollect ammo, and get additional lives. The scores will be kept in the top right of the screen, with the Team score being on the top and the player's individual score below that.

Regardless of the difficulty, the Tough Luck skull will be enabled from the start. With each new set, more skulls become enabled, more than one at a time. If one can stay alive, they will be awarded with higher scores and medals. Though each enemy class is worth a base number of points, earning medals can modify the player's tally as they go. Staying on lengthy streak without dying, and points will be augmented by a hefty multiplier.

Additionally, once a team has survived a Set, they will go on to the Bonus Round. Because it is only a Bonus Round, any deaths will not be subtracted from the overall point pool. However, since the Iron Skull is activated at the start, the team cannot respawn until time runs out. The Bonus Round provides players a chance to earn extra lives before the next Set. Extra lives will be unlocked every 2,000 points scored after the beginning of the round. It has also been mentioned by Bungie that the wave will consist entirely out of Grunts.

If you score total of 200,000 points on any map in the firefight mod, you will unlock an achievement, which is available for every map (except for the "night" missions, which will unlock an achievement for the their daily counterparts: so for example, if you play the map Crater(night) and score 200,001 points, you will unlock an achievement for the map Crater) making it a total of 8 achievements worthy of 10 points each.

Characters
The playable characters in Firefight are acquired by different means, most of them unlockable by earning achievements. Players are allowed to customize their emblem, background, colour (which now include formerly unavalible ones: black, olive ...) and Service Tag much like in Halo 3 multiplayer. The player's helmets is removable(with the exception of The Rookie), but it has no effect on gameplay in any way: your VISR is still available, even though it is a vision mod of the ODST's helmet.


 * Rookie: Unlocked by default.
 * Dare: Complete the Campaign on Legendary.
 * Buck: Unlock the Tayari Plaza Achievement.
 * Dutch: Unlock the Uplift Reserve Achievement.
 * Romeo: Unlock the NMPD HQ Achievement.
 * Mickey: Unlock the Kizingo Boulevard Achievement.
 * Sgt. Johnson: Comes with Pre-order of Halo 3: ODST.

Maps
Firefight will have ten maps to choose from (some are acquired by unlocking achievements). Known maps are as follows:


 * Alpha Site: Unlock the ONI Alpha Site achievement.
 * Chasm Ten : Unlock the Data Hive achievement.
 * Crater: Unlocked by default.
 * Last Exit: Unlock the Coastal Highway achievement.
 * Lost Platoon : Unlock the Uplift Reserve achievement.
 * Rally Point : Unlocked by default.
 * Security Zone : Unlocked by default.
 * Windward : Unlocked by default.

Trivia

 * Firefight plays out like Survival Mode from the Marathon games, Horde from Gears of War 2, Nazi Zombies from Call of Duty: World at War, and Survival Mode from Left 4 Dead in that they all have you try to survive and beat countless number of enemies over a long period of time. It is also similar to The Mercenaries from the Resident Evil Series, as it allows the player to unlock and use different characters online.
 * The player will be able to choose from four skulls at the start: Blind, Cowbell, the Grunt Birthday Skull, and IWHBYD; their effects are the same as in Halo 3. The skulls can be seen at the left side of the screen, the ones active will be highlighted.
 * According to the Bungie Day (7/7/09) Podcast, the last man standing will be able to revive his/her entire team by earning a Hero Medals.
 * According to firefight video clips, some of the enemies may come from Phantoms, while on Firefight map "Crater", some may come from "Monster Closets".


 * There are 7 characters to choose from for Firefight if you pre order and get Johnson.