Resonance stone

Resonance stones were psionic items that allowed a mind flayer to psionically imprint an emotion upon them.

Description
An individual resonance stone was an egg sized and round cut crystal or gem.

Powers
When activated, each resonance stone attempted to force the desired emotion onto anyone within twenty feet.

These stones were often used in illithid domiciles as decorates that simulated a chosen pleasant emotion. It is known that in this use that the stones were able to elicit satisfaction, anticipation, elation or satiation in nearby people. Illithid often treated them when they were used like this, like humans do with familiar smells in their homes.

However, these stone had another use of a defensive nature. They would sometimes be set in strategic locations around illithid colonies and elicit emotions such as fear, disgust, exhaustion or apathy in victims. The stones were used to induce fear and scattered across the 20 miles surrounding the illithid city of Oryndoll.