Here is the full list of all 26 SUPERHOT achievements. It takes around 20-25 hours to unlock all of the achievements on Windows.
Beat all Challenges.
Unlock all endless levels.
Kill over 1987 Red Dudes in endless mode.
Find all secrets.
Launch every app in the system.
Get RED ending in every level of SPEEDRUNrt challenge.
Get RED ending in every level of SPEEDRUN challenge.
Kill 3 Red Dudes with one rifle burst.
Kill 100 Red Dudes with a rifle.
Cut bullet with a katana.
Kill 100 Red Dudes with a katana.
Kill 100 Red Dudes using melee.
Kill an enemy by jumping on him.
Kill 100 Red Dudes with a shotgun.
Complete the game.
Kill 2 Red Dudes with one katana throw.
Score 100 headshots.
Kill 3 Red Dudes with one shotgun shot.
Kill 100 Red Dudes with a pistol.
Get back to the system after being expelled.
Become part of the community.
Complete SERV level.
Upload a replay on killstagram.com
Complete SUBWAY level.
Shoot down a bullet with a bullet.