Wallrunning

Wallrunning can occur when a player runs along a straight wall (either normally or by straferunning) while in contact with it. The player will be accelerated to a speed that is greater than normally attainable.

Wallrunning is triggered when: (The deathmatch tutorials at doom2.net suggest that it also works occasionally on walls aligned in other directions.)
 * The player is running north along a one-sided north-south wall, south along a two-sided north-south wall, or east along a one-sided east-west wall; and
 * The player is aligned either precisely parallel to, or 38.7 or 45 degrees away from the wall.

After a brief moment, the player will begin moving at a very high speed, ceasing only when the player stops running, encounters a corner, or changes direction (e.g. by being hit by a monster).

An agile player can exploit this bug as a speedrunning or deathmatch tactic, taking advantage of north-south and east-west walls to dodge projectile attacks or move quickly between distant areas of a map. Its use in deathmatch play is somewhat limited, however, because it requires that:


 * The level contain a straight north-south or east-west wall in the appropriate place(s);
 * The player determine which way is north, possibly during a fast-moving firefight;
 * The player rapidly orient themselves at the desired angle to the wall; and
 * The player wait for the acceleration to begin.

Demo files

 * [[Media:d213wrb.lmp|The wallrunning bug]] ([[Image:d213wrb.lmp|file info]]) on MAP13: Downtown