- "Your skills will be strained."
- — In-game Description
Hardened is one of the five difficulty settings in the Call of Duty series. It is harder than Recruit and Regular but easier than Veteran and Realistic. In all of the Call of Duty games that have achievements, the one achievement that can be unlocked only by playing on Hardened but not requiring Veteran is the large achievement for finishing the campaign on either of those difficulties.
On Hardened, players have less health than earlier difficulties, and the AI is slightly more accurate and effective. The enemies won't assault the player with as many grenades as on Veteran. In Call of Duty: Modern Warfare 2, the player's aim will kick up when shot on Hardened, albeit not as much as if the player was on Veteran. When killed by a grenade, the player will usually not be told what killed them. Additionally, when the player has little ammunition in their magazine, the player will not get a warning that says to reload.