This zone is special, as very few monsters will appear here (excluding the Red Ring Octopus). This zone is also where the four corner Beacons are located.
Deep Water zones limit the players movement speed immensely if they are swimming or using a Wooden Boat. They will move at around 1 MPH, making it extremely difficult to navigate in this zone. Experimentation reveals that it will take up to 3 real-time hours to cross the Deep Water zone in a Wooden Boat.
This slow procedure can be avoided by using the S.S. Valor. However, this is quite expensive to build, meaning it may be quite a while until one can effortlessly cross the Deep Water zone unless one is willing to sacrifice their time to use a Wooden Boat.
The Deep Water zone isn't entirely useless, luckily. Besides carrying corner Beacons and the rare Red Ring Octopi, the zone has a rare chance of spawning a Mermaid. These mobs have a set chance of appearing and are the only way of obtaining the Mermaid Scale, which is essential to crafting the Mermaid Outfit.