Setonaikai icon as seen from map selection menu
| โ | Armies and fleets clash on the same shallow sea. | โ |
| —Map description | ||
Setonaikai is a random map introduced in Age of Mythology: Retold - Heavenly Spear, named for the Seto Inland Sea between the islands of Honshu and Shikoku, in western Japan. It is an open hybrid map, covered in shallow waters that can be traversed by naval and land units alike.
Overview[]

| โ | Armies and fleets clash on the shallow Seto Inland Sea. A strong navy can control the fish supply and even besiege enemy bases, but only a powerful combined force will achieve victory. | โ |
| —Loading screen | ||
The most notable feature of this map is its amphibious terrain, which can not only be traversed by both naval and land units, but can also be built upon like regular terrain, with the added peculiarity that Docks can placed almost anywhere. This allows for some unusual strategies pitting land and naval units against each other in pitched battles, and gods with naval bonuses will thus have a key advantage on this map. The Japanese can find good use for their Umibลzus here, as they are able to teleport almost anywhere due to the shallow water terrain, which is considered the same as any other water for their ability. Likewise, the Chinese can make the most out of their Xuanwus here, as they have the ability to move much faster on water than on land, while Poseidon can use his Hippocampus naval myth unit to scout the waters more easily alongside the Kataskopos.
Starting hunt consists of Chickens and Green Pheasants, with other potential huntables including Deer, Spotted Deer, Serows, Crowned Cranes, and Monkeys. The shallow waters also contain fish (namely Herring). Japanese Wolves appear as predators, and Cows as herdables. Gold Mines appear on small islets scattered throughout the map, with additional Settlements and forests on the larger islands, while animals can be found both on land and in the shallows.
