Dead Silence

"Make less sound when you move."

- Perk description

Dead Silence is a Tier 3 perk featured in Call of Duty 4: Modern Warfare, Call of Duty: World at War and Call of Duty: Modern Warfare 3. The perk reduces a player's footstep noise significantly, allowing players to walk, sprint, and jump almost silently.

Call of Duty 4: Modern Warfare
Dead Silence is mainly used by players wishing to be stealthy; it lowers footstep sound so that it is almost silent - however it can still be heard, usually only picked up by high quality sound systems. It allows players to clearly hear other players' footsteps who are not using the perk. However, crouch-walking or going prone completely cancels noise created by movement. Dead Silence does not have an effect on weapon switching sounds, however. Even with the perk, falling from any height makes at least a slightly audible sound, and especially so from large heights where the loud cracking noise is still made. Rustling through bushes/grass also still creates noise.

Call of Duty: World at War
This perk is unlocked in Call of Duty: World at War at level 52. World at War has a much more effective usage due to the ability to disable ambient noise (Via Music Volume) and the announcers (Via Voice Volume), allowing for less interruptions in stalking players through sound.

Call of Duty: Modern Warfare 3
Dead Silence appears again in Call of Duty: Modern Warfare 3. It silences the player's footsteps and reduces the effect of the Recon perk, from 12 seconds to 6 seconds. To unlock Dead Silence Pro, the player needs to earn fifty close range kills, similar to Ninja and Scrambler from Call of Duty: Modern Warfare 2. Dead Silence can be canceled out by Sitrep Pro within close proximity. Dead Silence Pro negates falling damage, similar to Commando Pro from Call of Duty: Modern Warfare 2 and Lightweight Pro from Call of Duty: Black Ops.

Trivia

 * Melee kills count towards Dead Silence Pro.
 * Dead Silence was originally going to be an ability of one of the four planned multiplayer character abilities. However, the character models were scrapped and it was added as the Pro ability of Ninja..
 * Dead Silence Pro doesn't completely negate falling damage. You can still die if you're playing on hardcore and by jumping from a great height several times.