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However, in Call of Duty 3, since there is no Second Chance perk, the Syrette is the ability of the Medic Class. It is used to revive players who have been recently killed (Critically Wounded), although if the killed player committed suicide, died by artillery fire, or a tank shell, they are indefinitely "Dead" and cannot be revived. A white Cross symbol is shown over revivable teammates while playing as a Medic, and they are able to be revived until they respawn, or their body disappears.
The Perk-a-cola "Quick Revive" in Zombie mode greatly speeds up the reviving process, lowering the revive time from 4 seconds to 1.5 seconds. It can allow a player to help up a downed teammate while still under attack from zombies.
The Syrette also appears in Call of Duty: Black Ops, Call of Duty: Black Ops II, Call of Duty: Black Ops III and Call of Duty: Black Ops 4 for the same purpose. It is used in Zombies mode after someone is downed, and in Black Ops multiplayer when someone has the perk Second Chance Pro and is being revived by another player. It is, however, much faster in multiplayer than in Zombies. The player gets a 50 XP reward for doing so.
On PC, one can revive and reload at the same time.
In multiplayer and Zombies (with Quick Revive or the Quick Revive Persistent Upgrade), the downed player will be revived before the Syrette is injected.
Attempting to 'drop' the Syrette through the use of mods or console commands will result in the player being sent back to the main menu with an error, since the Syrette has no world model.