Bunnyhopping in Quake engine games
Quakeworld and older versions of Half-Life, Counter-Strike, and Team Fortress Classic utilise the same engine, so the techniques used to perform bunnyhopping in these games are nearly identical, Quakeworld has pogo stick jumping, while in the other games you have to jump right as you hit the ground. An acceleration is experienced in-air while uniformly turning in the same direction as the player is strafing. The act of timing your jumps to the exact moment when you hit the ground prevents the player from decelerating to normal walking speed. The strafing should also be timed in a particular way to the jumping for greatest effect. Using this technique unbroken, allows a player to gradually accelerate to speeds many times the typical running speed.
The speed at which one can bunnyhop is effectively limited by the turning radius, if too sharp a turn is made at high speed, speed is lost. In the old versions of Counter-Strike, the degree to which a player can make sharp turns while bunnyhopping without losing speed is regulated by the sv_airaccelerate server value. This value could be set to 0 to disable bunnyhopping, and had a maximum effective value of 20.
Because of the incredible speed bonuses achieved by a competent bunnyhopper in Counter-Strike, many players considered the technique, although merely a clever exploit of the game's physics, to be a cheat. In its day many Counter-Strike demos were recorded to demonstrate its incredible effectiveness in the form of trick jumps. Huge jumps could be performed, such as from building to building on cs_assault (sometimes sv_airaccelerate would have to be modified to perform such jumps, to allow higher speeds to be attained with smaller turning radii).
Bunnyhopping/strafejumping in Quake III Arena (and Jedi Knight 2 - which uses the Q3A engine), is considerably less effective than in Quakeworld and is a much easier skill to master.
Bunny hopping is still possible in Counter-Strike 1.6, and Source engine based games such as Half Life 2, Counter-Strike: Source and SiN Episodes: Emergence.
