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