Achievement - The Storm - 15G
"Escape from the Ship"
This is achievement comes from completing the prologue for the first time. Does not matter if you use a new character or imported one from the original. This chapter acts as a refresher in how to dispatch of zombies in this world.
One two things of note are the two thugs you will face off against.
The first is right after a cut-scene in which you see a Suicider coming out of some large cargo doors with a bunch of other zeds. You are automatically equipped with an assault rifle and positioned with him straight ahead of you so just unload on him and the explosion will wipe out a majority of the zombies. After that just deal with the thug and a few random stragglers that join the fight from the left side of the boat.
The second encounter is right at the end when you have to find an alternative route into the command deck of the ship. Once you drop down there will be a few zombies to dispatch as well as the now zombified captain of the ship. Simply handle him like any other thug (bobbing and weaving out of the range as he attacks and getting some cheap shots in until he goes down.). Otherwise use your special attack by holding down 'B' if you have enough for it and just finish him in seconds.
NOTE: Don't worry too much about searching the ship for things because you lose everything at the end of the prologue anyway. If you play in a Co-Op game before doing your own single player prologue and then go back to it, everything you earned in Co-Op will be gone once you finish it as well.