Coeus' Stone

As an imprisoned titan by Zeus, within Chthonia, Coeus is unable to leave the land until his banishment from all other realms has been served. With Chthonia soon opening up into the land that has surrounded it for many years, Coeus has began making his presence known to many mortals within the underground land. He's offered blessings in return for the pursuit of knowledge, as Coeus is the titan of the inquisitive mind. Unable to leave from Tartarus, the land at the lowest point of Chthonia before The Hollow Abyss, Coeus wishes to learn of anything he could get his hands on, often bestowing those he makes pacts and deals with one of his magical stones. 

These small items appear like stones, smooth and grey in appearance. They are able to fit into any pocket, for the most part, and can have etchings that resemble the same designs upon the Titan's body. The stone is made for a simple purpose, to relay important messages to Coeus to help pursue his thirst of knowledge. The stones are also capable of sending and receiving messages, both from Coeus and from other people that the inquisitorial Titan has made pacts with. Most adventurers born in Chthonia make pacts with him in order to communicate with one another. Coeus knows this, but as long as he has a majority of those he has made deals with respect him and give him important information of everywhere else within Chthonia, he does not mind what they do, outside of their given tasks. 

The stones come within pairs made in a similar way as Sending Stones, but the stones that are used by Coeus are devoured, so that he can communicate with any of his followers at will. Sometimes, he is even able to project an astral form of himself to anybody within his pacts of service. However, this is frowned upon by Melinoë, Goddess of Nightmares , who hunts after the projection before Coeus ends the communication between the two. The two however, get along, it's just that Melinoe does not wish to jeopardize the idea that Coeus may accidentally project too close to The Hollow Abyss , causing a Nightmare from inside to try and escape, in search of the titan. The two see each other as good friends, in fact. 

Coeus' Stone  Wondrous item, rare 

Coeus' stones come in pairs, with each smooth stone carved to match the other so the pairing is easily recognized. While you touch one stone, you can use an action to cast the sending spell from it. The target is the bearer of the other stone. If no creature bears the other stone, you know that fact as soon as you use the stone and don't cast the spell. 

Once sending is cast through the stones, they can't be used again until 1d4 hours has passed since the initial message. A total of 5 messages can be sent in one space of time, or two minutes worth of live communication. If one of the stones in a pair is destroyed, the other one becomes nonmagical.