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