Amulet of Druidic energies

This amulet is fashioned from a piece of black metal, with a symbol of a widening eye upon it. Whenever a creature casts a spell within 100 feet of the amulet, it begins to thrum subtly and glow with arcane energy of druidic origin as it adds to the power of the spell. When the command word is spoken near it though, it grants its wearer the power to control plants and beasts of all kinds, gifting them the magic of the druids of old.

Notes: From a Druid, Ranger, or Warlock