Vocal Connection

You give 2 creatures each a diamond worth 200 gp. The caster and the creature will now be able to communicate up to 20 miles. The spell last for 8 hours or until the spell is dispelled. If dispelled on a creature that is not the caster, the spell will end for that creature only. The caster will instantly know who got dispelled. If the caster is dispelled, the spell ends for all creatures.

At Higher Levels. When you cast this spell using a 7th level spell slot or higher, you get to choice 1 additional creature costing another 200 gp diamond.