The Seaworthy is a Structure that connects the Surface World and the Shipwrecked world of the Constant, or as the structure itself refers to, the 'Desolate Forest' and the 'Tropical Paradise'. It is not available in Don't Starve Together. It behaves similarly to Sinkholes.
In the Shipwrecked world, the player can find the Seaworthy already generated. It is found on an island generally far away from the center of the world. It is generated on the center of a square of four Wooden Flooring, with a single Skeleton nearby. It can neither be crafted or destroyed, meaning the location the Seaworthy is found in is definitive.
In order for the Seaworthy to function in a vanilla or Reign of Giants world that has not been merged, the option to be compatible with Shipwrecked has to be used, which can be done when initially creating said world.
In the Surface World, the Seaworthy does not naturally generate. In order to go to the Shipwrecked world, it must be prototyped using a Shadow Manipulator, under the Magic Tab. Doing so requires one Sea Worther Trinket, four Nightmare Fuel and four Living Logs. Traveling from the SW world to the Surface World does not come with a pre-crafted Seaworthy.
As the Sea Worther can be obtained from Hammering the Sunken Boat, or as a low 4.36% chance drop from fishing up the nearby Flotsam, it is theoretically possible to craft multiple Seaworthys in the Surface World, provided the player used the Wooden Thing multiple times to farm Sea Worthers or is lucky with Flotsam. The Seaworthy can also be placed in the Caves and the Ruins. Traveling to the Shipwrecked world will function normally, however returning to the Caves or Ruins will have the player enter the Surface World, near the associated Sinkhole. With travel distance between the Sinkhole and the Ruins in mind, it is therefore not recommended to place the Seaworthy in the Ruins.
When the Seaworthy is first used in either world, an option is given to create a new version of the other world. Another option given is to select an already existing, unmerged save file that features the other world. When save files are merged, the character that used the Seaworthy becomes the main character. Items that the owner of the previous file had in their inventory are stored in a Grave that can be dug up.
Followers cannot travel between the two worlds (including Abigail). Any unique character-specific items (Like Lucy the Axe or Willow's Lighter) will be replaced if it does not exist in the destination world. In addition to this, if one merges worlds with an already-existing save, unique character-specific items from the old character will disappear from the save entirely. This is likely to prevent players from obtaining these items with other characters.
Since Seasons pass by normally in the linked worlds, one can use Seaworthy to skip Seasons if they so wish by simply going through the portal and waiting in the other world. For example, if Dry Season were to start in a Shipwrecked world, the player could gather their things and go to their RoG/base game world until it has passed, provided the Season there is preferable. It should be noted that the two worlds do not necessarily have similar Seasons. For example, it can be Winter in a RoG world, but Monsoon Season in the SW world. The Wooden Thing can be used in either world to force the season to change to the beginning of either Mild Season or Autumn. Through this it is possible to match preferred Seasons.
If the Teleportato is used in a world, the connected world will not be regenerated along with it. This can allow for indefinite numbers of any non-renewable item by storing them in the other world, and regenerating the world the player wishes to obtain items from.
When two worlds are connected, Food Spoilage continues to exist at a normal rate in both worlds.
- In Don't Starve: Pocket Edition, the Seaworthy structure spawns as normal, but does not function and cannot be examined. This is probably due to the fact that the Shipwrecked DLC is its own app.
- Before it was implemented in the Wilbur vs. The Volcano update, the Malfunctioning Novelty Ride was used as a placeholder for the Seaworthy.
- When traveling through the Seaworthy, a distorted version of the Work To Be Done soundtrack can be heard briefly.
- In Adventure Mode, the Seaworthy will disappear immediately after placing it, which makes it impossible to launch Shipwrecked worlds there.
- When using a Seaworthy from Shipwrecked to create a new world to link to, the player will begin in that world on the day equivalent to their total survival time (the aggregate of all time survived in however many Shipwrecked worlds hopped). This can make predicting which Season to expect difficult.
- Followers can occasionally travel along with the player to the other side, though the exact requirements for this bug are unknown. Notably, Chester, Rock Lobsters, Glommer, Beefalo and perhaps more can glitch through. A duplicate of the respective mob will be present on the other side. This bug is shared by the other 'portals'; the Caves and Ruins Sinkholes as well as the Volcano. This bug seems to occur most often when 'portals' are used in quick succession while the player has an active Follower.