Hardline

Hardline is a perk available in Modern Warfare 2. It is a Tier Two Perk which is unlocked at Level 9, and allows the player to gain their killstreak rewards with one less kill. For instance, if the player had UAV Recon, Care Package and Sentry Gun as killstreak rewards, rather than needing 3, 4 and 5 kills respectively, they would only need 2, 3 and 4 kills. It is useful with all classes, although especially useful with classes with guns which carry little ammo, or ammo which is used up quickly, such as the Vector, because it means fewer bullets are needed to gain killstreak rewards.

Hardline Pro is unlocked after getting 40 2-kill streaks, regardless of getting a killstreak reward for it. It makes Deathstreaks activate one death earlier.

Trivia

 * It is generally regarded as a useless perk.