Hey guys this achievement is pretty easy unless you really struggle shooting little rats under the stress of having a time limit. But seriously, head to the shooting range in the Venice chapter, if you don't know where it is the guide shows you, its past the pub/bar and the strip club. You have to play the shooting range game three times, the first time you'll have one wave of rats, the second time you play (you have to pay the guy again each time you play) you'll have two waves and as im you can guess the third time you play you have to destroy three waves of rats. After completing the three waves head to the man and collect your special prize, the teddy bear. Opposite the shooting range is the child and hand over the teddy bear to get the achievement. For a visual aid please use the video below, I hope it helps, good luck!