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
All challenges completed
One hour in slowmotion
Died 250 times
All weapons and upgrades unlocked
Game completed
1000 enemies killed
Picked up 50 weapons
Second day completed
25 Doors destroyed
First weapon unlocked
First boss completed
Completed a level without slowmotion
100 enemies killed
Completed a level on first try
First level completed
First enemy killed
10 000 enemies killed