Find and use the hidden cache in 'Heat'.

Complete any level using only the knife to kill enemies.

Alert the enemy helicopter in 'All Ghillied Up' and take it down.

Kill 3 enemies in a row with your knife in the single player campaign.

Destroy 8 enemy helicopters in 'Heat'.

Get a kill with each type of handheld gun, explosive and launcher in the single player campaign.

Find 30 enemy intel items.

Kill Makarov and complete your mission

Complete the game on any difficulty.

Complete the game on Hardened or Veteran difficulty.

Complete 'Heat' and 'The Sins of the Father' on Veteran difficulty.

Complete 'All Ghillied Up' and 'One Shot, One Kill' on Veteran difficulty.

Kill at least 3 rappelling enemies in a single rope.