My first thought is Animal Messenger and Beast Sense. So you need a level 3 druid for this, with each of those spells prepared. They will be cast as rituals though, so no spell slots expended. 10 minutes casting time for each.
So let's say you have a wealthier city, and another wealthy city 10 miles away. For a variety of reasons, wealthier people and government officials might want to regularly communicate between the two locations. Normally they'd send riders between, or pay to use one shot spells to send a message.
What if instead they set up druid relay stations every 1.5 miles. So one station on either end, and five between the two cities, for seven total stations. Each station has shifts of two 3rd level druids.
Druid in City A casts animal messenger on a bird in a cage (10 mins casting time). Then casts beast sense of that bird (10 mins casting time). Bird is sent to next station down the line.
Animal Messenger says the bird travels 50 miles in 24 hours. So, in 45 minutes it travels a bit more than 1.5 miles. As it arrives, we have 15 minutes left of beast sense.
The next druid station down the way does the same, sending a bird back to the city. They do this every hour, each receiving a bird at about the same time.
Beast sense says you see and hear through the animal you've cast the spell on, and you cannot see or hear at your own body. It does not however say you cannot speak at your own body. So you can hear a message at a destination, and then speak that message at your own body.
By this means two people could have a near telephone call at a 1.5 mile distance. One side speaks, the other druid hears it, and vice versa.
But over the 10 miles, you have a longer delay, like a telegraph system. You send a message down the road, it's copied down, then it's sent down the road again, and so on until it reaches it's ultimate destination. I think it's roughly 6 hours to travel the 10 miles.
Now of course a rider system can run faster. But, can it run 10 minute messages? On a regular basis whenever you need it?
Maybe this isn't worth it, I don't know. I 'm just trying to play with how these two spells might synergize. Anyone have any thoughts on improving this system, or something else you might two combining these two druid ritual spells?
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