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