Here is the full list of all 35 Hotline Miami achievements. It takes around 12-15 hours to unlock all of the achievements on Windows.
Perform a 6x combo
Perform a 4x combo
Use a human shield
Perform a 8x combo
Perform a 10x combo
Perform a 12x combo
Beat the mainstory
Beat the epilogue
Beat the epilogue with secret ending
Get an A+ on any chapter
Get A+ on all the chapters
Kill 1989 enemies
Kill 99 dogs
Destroy 200 glass panels
Kill two enemies with the same brick in one throw
Kill three or more enemies with the same brick in one throw
Kill an enemy with a brick bounced against a wall
Throw a weapon at an enemy so that his weapon hits another
Collect all the masks
Wear all masks at least once
Unlock all weapons
use all guns at least once
use all melee weapon at least once
use all throwing weapon at least once
Perform every ground kill in the game
Complete chapter five barehanded
Die 1000 times
Unlock all achievements
Kill the crapping gangster with a fireaxe
Clear chapter 2 using Nigel the Bat
Find Jones The Crocodile
Kill the panthers using Brandon the Panther
Go to the car 60 times
Collect all the puzzle pieces
Solve the puzzle