Here is the full list of all 21 Party Hard trophies - there are 21 bronze. It takes around 8-10 hours to unlock all of the trophies on PlayStation 4.
Kill 20 people in a row
Kill 30 people without alarm in one level
Get you ass kicked for dancing
Play Party Hard 100 times
Kill 1000 people
Use traps 50 times
Hide 50 bodies
Pass level without traps 3 times
Escape cop 5 times
Die 100 times
Kill person who runs to call police 20 times
Kill all robbers in Casino level
Complete the game
Lose level with 1 alive person
Kill 50 stunned people
Kill 50 people by horse
Complete level in 3 minutes
Kill 15 people with one car
Poison 100 people
Complete level with FBI
Complete level without found body