Challenge

In Call of Duty 4: Modern Warfare, challenges are awarded to the player in five tiers. Each one is more challenging than the previous. While the "regular" give out 50-250 experience points, the weapon-based challenges can give up to 1000 XP when they are completed. Weapon challenges unlock special attachments and camouflages to attach to the weapon.

In Call of Duty: World at War, challenges are given to the player in eight tiers. Each one is also more challenging than the previous.

Boot Camp challenge's are seen as the least difficult with even the most mediocre players completing them by either Rank 55 in Call of Duty 4: Modern Warfare or Rank 65 in Call of Duty: World at War.

List of Weapon Challenges


 * Marksman Challenges-get a certain amount of kills with the weapon
 * Expert Challenges-get a certain amount of headshot kills.

List of Challenge Tiers


 * Boot Camp
 * Operations
 * Hero
 * Vehicle
 * Field Specialist
 * Killer
 * Humiliation
 * Elite