Alpha Site

Alpha Site is a map for the Firefight game type in Halo 3: ODST. It is unlocked by completing the ONI Alpha Site level in Campaign.

Layout
Alpha Site's general layout is a baseball-diamond shaped battle area, with players spawning on one side (the inner complex) and enemies dropping from Phantoms on the other (outer complex). There is a Sniper Rifle that spawns on this level, as well as a Shotgun.

The map was revealed first in the 7/31/09 Bungie Weekly Update. It takes place in the interior of the ONI Alpha Base.

Tips

 * There is a good tactic on this map to survive for a very long time, even on more challenging difficulties. The players have to enter the elevator and stay at the corners of the elevator. When Brutes show up, they will try to melee the ODSTs through the glass, but they will not damage the players. However, with a well-aimed melee, the player can hit the enemy through the glass via aiming at the weapon of the Brute. Also, while an enemy is hitting against the glass, another player can simply go behind the target and assassinate him (An excellent tactic for Brute Chieftains armed with Gravity Hammers).
 * If playing cooperatively, the above strategy is especially effective. If an enemy enters the elevator, the player who is not being targeted by the enemy can quickly assassinate the intruder.
 * A simple yet sound strategy is to use the side of the map that enemies do not spawn at as your "turf" as it has most of the power weapons, tons of normal ammo, and excellent cover and field of fire, as well as no attacks from behind to worry about.
 * The sniper rifle is very effective on this map to use in the above strategy.
 * Weapons placed in the elevator do not respawn between sets/waves/rounds. A great strategy is to place any weapons that you will want to use later on (Rockets, Sniper Rifle, Gravity Hammers, Fuel Rod Cannons) in that elevator, and then grabbing what you need when it is time.
 * Due to multiple advantages offered by the map, Alpha Site is one of the favorite Firefight levels, practically to gain achievements Vidmaster Challenge: Endure.