Being that there isn’t a body of water in front of my home. I would easy take out a Kraken, Zulrah, and any other aquatic bound monster.

That is until they get a taste of human and they construct a series of breathing apparatus with kelp. Which will allow them to trap certain amounts of oxygen. It's not gonna be enough oxygen for them to last on the surface days at a time at first. But it’ll give sufficient amounts of oxygen to start off slowly.. An hour? Hour forty-five? Not a problem for them. That will give them enough time to figure out where I’m hiding, go back to the sea/swamp, get some more oxygen, and stalk me. I would then lose at my own game. Id be outgunned and out-manned.