Backwash

Backwash is a multiplayer map featured in Halo 2. It was added to Halo 2 as part of the Maptacular Pack.

Summary
"Attended to by automated systems this Forerunner structure plays host to a violent but mist-shrouded conflict."

Delta Halo's primary Flood containment facilities resided in remote regions of the ring, including a series of vast bogs and swamplands. It is believed the Forerunners did this to discourage potential intruders or at least obfuscate the truth of the facility below. At some point, the Flood breached the containment facility, leading to an outbreak and formation of a Gravemind. It is unknown whether a system malfunction or outside meddling led to the breach. Backwash is set in this location, resembling the Halo: Combat Evolved campaign level 343 Guilty Spark.

Veiled in mist and alive with the chattering of unseen fauna, Backwash is a sodden valley in a seemingly boundless swamp. Forerunner technology, illuminated by eerie light, still hums with life. Shapes move in the dense fog and in the midst of this dank heat, it's hard to tell friend from foe. Hills and hummocks make the boggy terrain treacherous and difficult to navigate. Marksmen can stand unnoticed and unchallenged in the banks of fog or take shelter in the confines of Forerunner installations surrounding the mire. Ambient life referred to by Bungie artist Justin Hayward as "glow bugs" crawl around the map, and 2401 Penitent Tangent can be seen flying around the map.

Backwash is one of the smaller maps in Halo 2, made even smaller by the presence of thick fog on the map. This enables the presence of equipment such as the energy sword and active camouflage.

Matchmaking removal
Backwash was removed from Halo 2 Matchmaking in the April 2006 Matchmaking Playlist update, due to problems with the Xbox loading the fog covering the map. Backwash was the only map to ever be removed from Halo 2 Matchmaking.

Hidden message
There is a way to get out of the level, but it requires super-jumping or a Spectre. With a person, get him/her to Superjump over the invisible wall on the hill, then get them to stand on top of the base (red or blue). Get them as close as possible to the wall and then sword cancel up onto a small spot on top of the base. You can now sword cancel (try it a lot) through the wall. Then, walk through something that looks like a large amount of roots (surrounds the outside) and look for edge of the level. Then walk around until you find red ground. The message is very large, written in blood, and says: IT'S LOOKING A LITTLE ROUGH OUT HERE. (Possibly because of the mold, fog, etc.) Also, go to the far right and there is a message that simply reads, "HERE."

To do it with the Spectre, go to blue base and jump on a small ledge that is right next to the invisible wall. Have the driver put on a severe handicap (if you don't have an overshield) then ram into you. If done correctly you will be smashed through the invisible wall.

Strategy
Try to limit use of all Covenant weapons on this map, as the fog shows the plasma bursts quite distinctly. In particular, this means that you should either not use the energy sword at all, or keep it hidden until right before you attack. Using Active Camo up on this level will not solve this problem, as the energy sword is still visible under Active Camo in Halo 2.

Production notes

 * During production of the level, 343 Guilty Spark was originally going to be the monitor flying around the map. However, the monitor was changed to the red glow of 2401 Penitent Tangent when it became apparent 343 looked too much like a plasma grenade flying through the air.
 * The presence of 2401 was the inspiration to place the Sentinel Beams on the map.
 * The ambient animal noise found on this map was originally recorded for Halo: Combat Evolved.
 * Players will not spawn with grenades of any kind on this map (though they can be picked up). Due to the map's very small size, players tended to spawn and immediately spam grenades to the other side of the map. From a performance consideration, gametypes like King of the Hill would tend to lag considerably when all players had grenades.
 * One of the design goals for the production of Backwash was the creation of a small-scale, 4-player map that would work well for Slayer. The production group for the map came up with the idea of creating a map set in a swamp similar to the mission 343 Guilty Spark, of Halo: Combat Evolved, in which players could use fog and murk to hunt each other. Major references for both the visual and auditory aspects of the map included Rambo.
 * The design of Backwash is not particularly complex, as the intention was to create a simple arena. This led to some issues with design as players could see one another from opposite sides of the map, and the long sightlines proved troublesome for the Xbox hardware available, leading to concessions and cuts on both art and design.

Trivia

 * Though the sounds made by 2401 Penitent Tangent on this level are similar to sounds from 343 Guilty Spark's files, they were recorded by a different voice actor and are therefore distinct.
 * Along with Desolation, this is the only level in the Halo trilogy to spawn a Sentinel beam by default.
 * There is an easter egg called the Hidden Gargoyle on the map.
 * The plants that are seen on the level resemble those seen on the level 343 Guilty Spark, mainly because of the environment being a swamp. The plants are also seen aboard High Charity during the levels Gravemind and High Charity in the outdoor areas.