Invisible wall
From Halopedia, the Halo wiki
Invisible Walls are a term used by many Halo 2 players who do tricks and glitches, usually involving exiting to the outside of a level. In most cases it is impracticle to try to get through one in an actual game when your trying to win. The invisible walls act like any other wall, with the exception that they are of course invisible and usuall encircle the map. Often times just outside of an invisible wall is a kill barrier, which is best described as a zone in which once you walk into it, you die suddenly for no appearent reason, although most of the time it says you fell to your death. There are ways up and or through these invisible walls, however as climbing outside of the level in a match is considered cheating, no details will be given at this time.
Getting Past Invisible Walls
Sword Flying
The sword lunge is a very practicle way of getting passed invisible walls. With one player on the other side of the wall, you can lunge/cancel on him until you go through. If there is a height limit on it, such as the invisible wall on the top of Gemini, you can lunge upwards and over the wall by being farther bellow the "Lunge Host".
Sword lunging is not the quickest way of getting past an invisible wall, however, but it takes less know-how to accomplish. This will not work on every wall either.
Super Jumping
Super jumping is a glitch in the game that makes it possible to get to higher areas within levels, places that are not supposed to be gotten to without a Banshee, or at all. They are useful in getting passed invisible walls that Banshees cannot get out through, or going on foot. The super jump on Ascension is a good example of getting passed an invisible barrier, although, the two person Banshee trick will work, it is easier to do the super jump during matchmaking.
Super jumps can take time to learn, and are not always easy to accomplish on first tries. They can be tricky, making the player go through several ellaborate tasks before being done. Jumping on different ledges and using perfect aim and timing.
Although it is easier to get over most invisible walls witht he super jump, it is harder than the sword lunge, unless you know what you're doing.
