Here is the full list of all 42 Gunpoint achievements. It takes around 6-8 hours to unlock all of the achievements on Windows.
Create a custom mission with at least one objective.
Publish your personalised epilogue.
Complete the game.
Shoot Fritz Gessler.
Beat Fritz Gessler to death.
Knock Fritz Gessler out with a punch.
Intimidate Fritz Gessler into surrendering.
Catch a guilty man at the expense of freeing an innocent one.
Use the Longshot to make a guard unintentionally shoot another (outside of the test lab).
Use the Gatecrashers to kick a door through a window.
Use the Gatecrashers to kick a door into a guard.
Use the Gatecrashers to kick a door off its hinges.
Mock the chief of police at a critical moment.
Knock a guard out by opening a door into him.
Help justify my early, not entirely wise choice of game name by holding someone at gunpoint with the Resolver.
Upgrade your battery capacity to the non-figurative max.
Upgrade your Bullfrog Hypertrousers to maximum jump strength.
Conceal your presence at the DataSec break-in from Mayfield.
Use the Hushcracker to jump through a window silently (outside of the test lab).
Tell Gessler that Rooke's hired you to betray him.
Jump into an Enforcer to knock him through a window.
Use the Prankspasm to knock out someone who isn't standing near a power socket (outside of the test lab).
Get knocked down by an opening door.
Use the Dropshot to land silently from a great height.
Use no violence at all on a mission that has guards.
Complete a mission that has guards with no violence, witnesses or loud noises.
Use the Crosslink to create an infinite loop that burns itself out.
Upgrade your Bullfrog Hypertrousers to pounce instantly.
Wire an elevator button to trigger something when the elevator arrives.
Leave no living witnesses to your presence on a mission that has guards.
This is an achievement in name only. No-one admires you for punching a guy that many times.
Complete a mission faster than I can.
Voluntarily tell Katie the truth.
Chicken out of telling Katie the truth at the last minute.
Steal Gessler's technology for Rooke.
Complete the police chief's missions without incriminating yourself.
Free an innocent man at the expense of catching a guilty one.
Defeat Gessler by rewiring his gun.
Knock Fritz Gessler out of his office window.
Kick Fritz Gessler's office door into him.
Notice the story doesn't necessarily gel with the mechanics. Become qualified games journalist.
Slam Fritz Gessler's office door into him.