Shrek Forever After

This achievement will unlock at the end of the Docks level (the fifth level) after you unhook the second anchor. Watch out for the crabs, as they can tip your boat towards the whirlpools (you can go most of the way into the whirlpool without dying, so use this to your advantage by dodging the crab cage).

Another thing I would mention is that for some strange reason, this achievement popped about 5 minutes after I completed the level, so if it doesn't pop for you, take a break for a few minutes. You'll likely get it if you wait for a while.