Knife

The Knife
Although the knife is technically the melee weapon for the spy class, it is common knowledge that it is considered to be the spy’s primary tool. The model featured for this weapon is that of a common Balisong knife, more commonly known as a Butterfly knife, and retains many of its generic features which make up this style of knife. The Knife its self is the lowest damaging weapon of all the game’s classes, however. A stab from behind will result in an instant kill, thus making it a deadly tool when in the right hands.

The Backstab
The most commonly associated form of attack associated with the spy is the backstab. Although there are many ways of performing it, the standard way involves positioning your character behind an enemy player, and stabbing into their back with the knife. An animation will play show you shoving the knife into his back, and the enemy will die instantly. The spy will be awarded two points for this type of kill. There are many types of backstabs which are often referred to as trick stabs. Although they all act on the same principle that an enemy is stabbed in the back; each of these trick stabs are executed quite differently to each other stab.

The Animation
At launch of the game, the backstab animation illustrated the spy lifting his knife behind the back of the player and proceeding to stab downwards into the player in a dagger like fashion. Although this animation looked very impressive, it soon became apparent that it had disadvantages, too. One main problem that this animation created was the delay between the action and the stab being performed. Spies often complained about the duration of the animation which often resulted in a missed stab, or corrupted efficiency. Once the animation was triggered, there was still time for the enemy player to move out of the way of the incoming stab, which would have been a definite kill had the animation not delayed the stab. During chain stabs the triggered animation often meant inconvenience to the spy, as it meant staying in the hazardous areas for longer periods of time.

Bypassing the animation
This animation was considered such an inconvenience to spies, that much discussion within the spy community at the time was directed towards bypassing the long animation which caused the troublesome delay. The two most frequently used variations of animation bypassing were known as the quick stab and the running poke/pokestab.

The Quickstab
The quick stab was performed by purposely missing the target, so that the fast animation was triggered. With the knife extended in this way, the player was able to move their crosshair across the back of the enemy player, resulting in a much faster backstab.

The Pokestab
This style of animation bypass worked using the same physics as the quick stab and had the same effect; however, it was performed quite differently. By running towards the player and stabbing early, the knife would have not been in range to successfully trigger an animation, or a stab. Once the player continued moving forwards, the extended knife would move into the enemies back, triggering the kill. Lower skilled spies quite often performed this stab without realising.

February 24 2009, The Scout Update
The scout update also came with many fixes and balancing issues for other classes. One of the biggest changes to the game during this period was the changed backstab physics. The patch notes on the particular update feature the statement “Changed backstab handling to fix facestabs” Although there was no direct evidence to support whether or not the facestab issue was fixed, players soon became aware that the traditional backstab animation had been replaced with a faster alternative. This caused some controversy amongst the spy community. Many newer spies and some older spies loved the new instant stab, it was much easier to perform, however many other older spies disliked it claiming it "rewards less experienced spies with an easier backstab, while hindering more experienced spies by eradicating more advanced types of stabs." The new backstab handling affected most experienced spies who were used to bypassing the long animation. These spies soon had to change their style as landing a successful stab with the new stab handling meant that the spy had to be almost in direct contact with the enemies back, in order to create a backstab. It soon became apparent by many that the new stab physics were influenced strongly by the workings of the Combat Knife from Valve product Counter Strike v1.5. The stab would trigger immediately once instructed and a much faster version of the traditional animation would follow. This animation would not play if the server had Critical hits turned off.

May 21 2009, The Spy Versus Sniper Update
On the release of this particular update the stab physics were changed once again. The most noticeable change to the animation was that the spies arm would rise above the enemies back if a backstab was possible. Many spies found this useful as stabbing without a raised arm would generally result in a regular low damage stab and often disastrous consequences would follow. The animation was not needed to actually score a backstab however, it just indicated it was possible. The backstab angle was also tightened so you could only stab an enemy if you were literally behind them. This made sidestabs impossible.

June 8 2009
Stabbing from the side was made possible once more. Valve added the following into their patch notes: “Fixed a couple of cases where viable backstabs would fail.”

Trick Stabs
A trick stab is a variation of the generic backstab. Quite often trick stabs are used as an emergency measure or to embarrass an unsuspecting/inexperienced player. The most famous of these is the stairstab, where you jump over an enemy as he runs up a flight of stairs and stab him in the back.

Other uses
Stabbing at sapped sentries makes them destruct faster. Many spies will stab a sapped sentry rather than shooting it, as the revolver does less damage to a sapped sentry than the knife.