Here is the full list of all 40 Crysis achievements worth 1,000 gamerscore. It takes around 15-20 hours to unlock all of the achievements on Xbox 360.
Complete all Secondary Objectives
Kill 10 enemies by throwing an object at them
Customize a weapon to use all 5 modification points
Use all weapon attachments
Tag 30 enemies using the binoculars
Reach the end of 'Onslaught' in the tank you started with
Kill an enemy Nanosuit soldier with a Strength punch
Kill 400 enemies
Help the marines evacuate
Kill 20 enemies with grab
Complete 'Core', 'Paradise Lost', 'Exodus' and 'Reckoning' on Delta difficulty
Complete the game on any difficulty
Complete the game on Hard or Delta difficulty
Secure victory in the Battle of Lingshan
Defeat the flight deck invader
Perform a kill with every firearm
Escort Prophet to safety
Escape the mysterious structure under the mountain
Complete 'Assault', 'Onslaught' and 'Awakening' on Delta difficulty
Defeat General Kyong
Enter the mines
Destroy 5 helicopters
Proceed to the mining complex
Kill 200 enemies
Complete 6 Secondary Objectives
Secure the train station
Destroy 5 enemy tanks
Kill an enemy 200m away
Destroy the cruiser
Destroy all AA guns around the harbor
Complete 'Contact', 'Recovery' and 'Relic' on Delta difficulty
Board the VTOL for extraction
Infiltrate the excavation site
Speed sprint 3km
Regroup with Prophet upriver
Perform 5 consecutive kills without being spotted by an enemy
Rescue the hostage
Complete 3 Secondary Objectives
Discover the fate of the Lusca's Call
Pick up an animal