Here is the full list of all 23 A.V. achievements.
Completed the full game
Finish the game with the Velocity Instrument
Finish the game with the Elasticity Instrument
Finish the game with the Initiator Instrument
Finish the game with the Freezer Instrument
Finish the game with the Deactivator Instrument
Finish the game with the Scrambler Instrument
Unlock all of the game's ending sequences
Enter Zone 2
Enter Zone 3
Complete the game without being seen
Take more than 30 minutes to complete the Tutorial area
Complete the Tutorial after unlocking the achievement “HOW DO I REACH THESE KIDS?!”
Destroy yourself as CHIP commands
Jump into the Reactor’s Unguarded Pit of Death
Complete the game using one Ping, only
Complete the game in less than one hour
Freeze 15 or more enemies at a time
Activate all six Pylons in Zone 1 or Zone 2, and activate the Distribution Pylon to listen to the full track
Activate all six Pylons in Zone 1 or Zone 2 in binary numerical sequence
Go back and repeat the same sequence through Zone 3 after reaching the Pylon platform
Get spotted by at least 50 enemies without being destroyed
Pay a visit to the poor, neglected TERRY in Zone 1, just to give him some excitement for once