Damnation

Damnation is a multiplayer map in Halo: Combat Evolved. It is one of the few non-symmetrical maps and incorporates both a high and low flag base, providing heavily vertical gameplay. It is highly popular on the Oddball and Team Slayer gametypes.

Summary
Damnation takes place in a Covenant facility devoted to the controlling of water flow on terrestrial surfaces. There are three separate streams of water flow down, into an abyss in the main chamber, with many interconnecting platforms, bridges and walkways hanging dangerously close to the pit. Other rooms are mostly empty, with the exception of Covenant communication nodes and Covenant supply cases.

Bungie.net Hints:

 * During CTF events stay close to the flag locations and snipe across the high teleport road and the low dam crossing. Communicate well and the flag is yours, as it is easy to attack the flag bases from multiple sides at once.
 * Use the two Sniper Rifles to surprise and effectively suppress opponents. There's a good hiding place near the uplink crate.
 * Watch your step! There are a lot of areas on Damnation where you can walk off a ledge and die. Pipes, on the other hand, can be fun places to hang out and get the drop on someone.
 * It was thought that to hop to the pit area from the falls bridge area was impossible, though you can do it the other way. This is actually incorrect - a fairly seasoned Halo: CE player can achieve this jump from the middle fall bridge to the pit area that contains the coveted rocket launcher. This is done by simultaneously performing two tasks: 1) walking over the Overshield power-up and 2) bouncing a grenade at the wall so that it blows up directly beneath your feet. If timed properly, the grenade will propel the player over the ledge as the Overshield is "powering up", therefore causing no damage to the player's health and maintaining the Overshield intact. Some things to remember: 1) the fuse times of plasma grenades and fragmentation grenades are different (fragmentation grenade will blow up almost immediately when this specific grenade toss is performed, as it is programmed to detonate almost immediately after "settling" on the ground; plasma grenade will take approximately 2 seconds post-settling to detonate); 2) if timed perfectly, you can throw the grenade at the wall as you are running full-speed at the wall while powering-up with the Overshield just as the grenade detonates (again, WHEN you throw the grenade at the wall depends on whether you are using a plasma or fragmentation grenade) - this is most efficient and helps to decrease the chance that you will be killed by an opponent noticing you prepping for the jump; and 3) getting INTO the pit area does not necessarily mean you are going to GET OUT, as this is one of the most highly-contested spots on the map, with constant grenade detonations going on and players monitoring the re-spawn of the Rocket Launcher.

Trivia

 * Although the map is stated to be on Installation 04, there is no Halo in the sky or any sign of the planet Threshold or its moon, Basis, though if you look into the water outside the map, you can still see what looks like the Halo ring reflected on its surface.
 * Some of the pipes drip a green liquid, presumably the same as the liquid that can be seen in levels with the Flood in Halo: Combat Evolved.
 * If you´re playing Oddball and throw the skull outside the map via a window, it will keep going down infinitely, unless it "respawns".
 * The short video Red vs Blue: Animated, made by Rooster Teeth Productions, features a form of Damnation. The small area where the Rocket Launcher respawns is set as the initial area that the characters are in.
 * This map, along with Beaver Creek, Hang 'Em High, and Timberland will be featured in Halo: Combat Evolved Anniversary as remakes.