In the current story, the PC's are chasing after a traitor from their kingdom. They are working with the Spymaster to chase him down and catch or kill him. The Spymaster is going to suggest a pincer move to stop the traitor from simply running away.
I need a way the Spymaster can keep in contact with the party over long distances (10s of miles at the least). Preferably instant but it doesn't have be two-way, just short messages to each other would be perfect.
Are there any spells or magical items in 5th Edition D&D that can do this?
Homebrew answers will be accepted if they have been play-tested.