Kill 25 unaware enemies.

Find 25% of GPS caches.

Kill 50 enemies with the bow.

Perform 50 headshot kills in the single player campaign.

Complete one optional tomb.

Kill and loot 10 large animals (deer, boar, wolves).

You completed the game

You used a rat tunnel

You completed all the Slackjaw side missions

You recovered your belongings

You brought about the Lord Regent's fall from grace by broadcasting his crimes

You fought 5 enemies at once and none of them survived

You killed 6 enemies in less than 1 second