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I'm about to start running a homebrew seafaring campaign in which my PC's will spend the vast majority of the narrative travelling on a boat, far from the mainland, on a diplomatic mission to explore a newly discovered archipelago.
While they are geographically distant from their homeland and their country's authorities (initial quest givers), and constantly on the move, I would nonetheless like there to be some limited channel of communication between the ship and the mainland - basically, a way that they can send progress reports from the ship back to the government and receive fresh commands / periodic updates on what's happening at home.
The way that I've hit on doing this is through something like a magic pair of linked cabinets, one of which is on the boat and one on the mainland (inspired by Harry Potter). Objects (in this case written documents) which are placed in one cabinet disappear from that cabinet, when it is closed and appear in the other. These cabinets would be small enough to prevent people travelling through them.
I currently plan on homebrewing this but, can such an effect, or something very similar to this, be achieved through any official spells or items?
Solutions should take into account:
- The boat will be constantly moving - the mainland will not know the PC's location in advance to send things to them.
- There will not initially be any high level magic users on the boat - though there may be high level NPCs on the mainland. The PC's will start the game at a low level and I don't want to populate the boat with party-allied NPC's that are more capable than the PC's themselves are. Otherwise why would such an NPC stay on the boat whenever they make landfall, rather than boosting the PC's landing party?
- my preference would be for a system that transports actual physical objects (such as written documents), rather than provides some form of psychic connection.