Here is the full list of all 20 Shank 2 achievements worth 200 gamerscore. It takes around 15-20 hours to unlock all of the achievements on Xbox 360.
Complete Campaign Mode on Hard difficulty
Execute 150 kills with the baseball bat
Rescue 50 Civilians From The Militia
Buy everything in Survival Mode
Kill 100 enemies using the shovel
Stay alive for 15 consecutive Survival waves
Kill 50 enemies with the heavy object smash
Do 30 counters in one Survival match
Perform 100 Machete Counter Kills
Get 30 firetrap kills in one Survival match
Complete Campaign Mode on Normal difficulty
Kill a Survival Boss with no traps or grenades
Perform 60 Pistol Counter Kills
Reach the zombie wave in each Survival map
Find the kitchen sink and kill someone with it
Do 10 combos of 20 hits or more
Beat a Campaign level with no ranged attacks
Buy nothing for 10 straight waves of Survival
Kill 12 enemies
Defeat all the waves in any Survival map