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