Tagging is a game play mechanic in the Counter-Strike series to determine the mobility slowdown a player receives as a result of being shot.
Counter-Strike and Counter-Strike: Condition Zero had heavy tagging for all guns. When being shot with the Desert Eagle, shotguns or rifles whilst standing still, a victim received knock-back except for leg shots. The other weapons do not cause knock-back. In Counter-Strike: Source, the tagging effect was added to grenades, but was reduced for all guns and the knock-back effect removed. Also the acceleration after being tagged occurs at a reduced rate.
Starting with Counter-Strike: Global Offensive, the slowdown effect is determined by the "mobility value" of the the player's currently equipped weapon and the weapon you are shot by. Additionally, the effect is cumulative and applies more heavily when the player is hit multiple times in quick succession. The lower the weapon's mobility value is, the higher the tagging rate and the more intense the slowdown effect is on the player. This means equipping weapons with a high mobility value, like the Glock-18, will reduce the slowdown effect when the player is shot. Conversely, equipping a weapon such as the AK-47, will mean the player is adversely affected by high slowdown when shot. Grenade tagging is also now dependent on the damage taken by the player.
- In Global Offensive, the buy menu displays a weapon's tagging power (Stopping Power) in numbers 1-5. However, game files suggests that stars (★☆☆☆☆ - ★★★★★) were originally intended to be used to represent the stopping power, but were scrapped.
- "What is Tagging and how does it work?" by CS:GO Official on SteamCommunity.com