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.
Get RED ending in every level of SPEEDRUNrt challenge.
Find all secrets.
Kill over 1987 Red Dudes in endless mode.
Unlock all endless levels.
Launch every app in the system.
Kill 100 Red Dudes with a rifle.
Get RED ending in every level of SPEEDRUN challenge.
Kill 3 Red Dudes with one rifle burst.
Kill 3 Red Dudes with one shotgun shot.
Kill 100 Red Dudes with a shotgun.
Kill 2 Red Dudes with one katana throw.
Kill 100 Red Dudes with a katana.
Kill an enemy by jumping on him.
Complete the game.
Score 100 headshots.
Cut bullet with a katana.
Upload a replay on killstagram.com
Become part of the community.
Get back to the system after being expelled.
Kill 100 Red Dudes with a pistol.
Kill 100 Red Dudes using melee.
Complete SERV level.
Complete SUBWAY level.
Shoot down a bullet with a bullet.