Overkill

"Carry two primary weapons, no pistol."

- Perk description

Overkill is a Tier 2 perk in Call of Duty 4: Modern Warfare, Call of Duty: World at War and Call of Duty: Modern Warfare 3 that allows the player to carry two primary weapons, instead of a primary weapon and secondary (sidearm, machine pistol, or launcher). When using Overkill, the first primary weapon determines movement speed and character appearance, as it always does. The second weapon chosen when the perk is active cannot utilize any camouflage, and has no effect on mobility or appearance, with the exception of the gun being visible on the player's back.

Call of Duty 4: Modern Warfare
Overkill is unlocked at level 38 in Call of Duty 4: Modern Warfare. Perks that affect weapons will affect both primary weapons a player carries, as all perks apply to the player and not their weapons. A player using Overkill will use an M9 during Last Stand in Call of Duty 4: Modern Warfare.

Call of Duty: World at War
It is unlocked at level 56 in Call of Duty: World at War and is the same as it was in Call of Duty 4. When in Second Chance a player will use a M1911 in Call of Duty: World at War if they have Overkill equipped.

Call of Duty: Modern Warfare 3
Overkill allows players to carry two primary weapons, as in previous Call of Duty games, though the second primary weapon is incapable of accepting attachments or camouflages, but Proficiencies can still be applied. Overkill Pro allows the use of an attachment and application of camouflage on the second primary. To unlock Overkill Pro, the player must earn 120 kills with their second primary weapon. This perk is featured in the Grenadier default class giving the player a G36C and PP90M1. It is unlocked at level 47, making it the last of the Tier 2 perks unlocked.

When first switching to the player's secondary weapon, the weapon's switch time is slower, as the first draw animation is the same as picking up the weapon off the ground.

Trivia

 * If the player is in a private match and the rules are set to no perks, the player's secondary weapon is replaced by an M9 in Call of Duty 4, an M1911 in World at War and a USP .45 in Modern Warfare 3.
 * It is the only perk not compatible with the Specialist Strike Package, though it can be one of the player's three starting perks.
 * There are sound files for the acquisition of Overkill when using the Specialist Strike Package, but is never used because of its incompatibility.
 * In Modern Warfare 3, when the player gets "Overkill Pro: IV", there is an image showing the perk turning to its Pro version, similar to Modern Warfare 2. This is the only perk in the game to do so.