Here is the full list of all 19 The Hong Kong Massacre achievements.
Complete the first and second day without dying
Complete first day without dying
Game completed
All challenges completed
One hour in slowmotion
All weapons and upgrades unlocked
Died 250 times
Second day completed
1000 enemies killed
First weapon unlocked
First boss completed
Completed a level without slowmotion
Picked up 50 weapons
25 Doors destroyed
100 enemies killed
Completed a level on first try
First level completed
First enemy killed
10 000 enemies killed