The Great Ocean or Great Western Ocean, the southern section of which is also sometimes known as the World Pond, is a giant ocean between the Old World, Araby and The Southlands - and the New World (Naggaroth and Lustria). The Great Ocean is roughly equivalent to the Atlantic Ocean in the real world.
The Great Ocean has many smaller seas connecting to it, such as the Sea of Malice and the Sea of Chill near Naggaroth, the Sea of Claws and the Sea of Chaos and the Black Gulf near the Old World. The Great Ocean also surrounds Ulthuan and Albion and connects with the Far Sea and the Sea of Dread at the southern capes of Lustria and the Southlands respectively, two other large oceans.
- The Sea of Claws is located between Norsca and the northern Empire and Kislev, a part of the Great Ocean. Equivalent of the North Sea in the real world.
- The Sea of Chaos is north of Norsca, similar to the Arctic Sea, stretches across the north of the world to Naggaroth, south of the Chaos Wastes. Part of the Great Ocean.
- The Kraken Sea is between central Norsca and the Chaos Wastes, part of the Great Ocean/Sea of Chaos.
- The Frozen Sea, also known as the White Sea, is part of the Sea of Chaos/Great Ocean between eastern Norsca and the Chaos Wastes, and freezes with pack-ice in winter.
- The Sea of Malice is a large sea, equivalent of the inner Hudson Bay in northern Naggaroth.
- The Sea of Chill is analogous to the outer Hudson Bay and is located near northern Naggaroth.
- The Sea of Serpents is between the central New World and Ulthuan.
- The Straits of Fear are south of Naggaroth, between the central New World in Naggaroth's south coast.
- The Gulf of Medes is the gulf that separates south-eastern Araby from The Southlands.