Fully mod and completely upgrade all weapons.

Kill 40 enemies with the shotgun.

Complete all optional tombs.

Find 75% of all documents.

Find 75% of GPS caches.

Kill 75 enemies with the rifle.

Kill 25 unaware enemies.

Purchase all skills in one category.

Force an enemy to drop dynamite that kills two people when exploding.

Kill 50 enemies with the bow.

Find 25% of GPS caches.

Kill and loot 10 small animals (rabbits, chickens, rats).

Collect 25% of all relics.