The Shadow Emerald was a large, green-like gem the size of a human hand. The emerald communicated its abilities to those who wield it, and such an individual must be a mortal, humanoid creature with at least a charisma of 20 and not beholden to Rhoswen in any way. The Shadow Emerald granted the following abilities:
- The wielder constantly knows the location to Queen Rhoswen if located on the same plane, as if with a status spell as long as they hold the emerald in their hand
- The Shadow Emerald produces a constant antilife shell effect, except it only affects Queen Rhoswen.
- When within line of sight and no further than 30 feet from Queen Rhoswen, the Shadow Emerald can be activated as a full-round action when grasped in one hand. The artifact must be continuously held to function properly. Every round as a standard action, the Shadow Emerald drains vitality and magical essence from Rhoswen, causing 3d8 points of damage and the loss of some magical power. This effect cannot reduce Rhoswen to negative hit points
The Shadow Emerald contained a shard of the essence of Queen Rhoswen, secretly pulled from her during the initial ritual that severed her and the Fellnight Realm from the First World as a method of fighting the Fellnight Queen should she ever escape her imprisonment. It was entrusted to the first bloduwedd Warden and passed to her successors until it came to Warden Halia’s charge.
Before her death, Warden Halia gifted the Shadow Emerald to the group to use against the Fellnight Queen. It was gifted temproarily to Nessa, who met the artifact’s conditions of use. Nessa used it to great effect during the end of the Fellnight Conflict in the battle with Queen Rhoswen, and it was instruemental in draining the fey queen’s essence so she could be destroyed.
A short time later, during the Ritual of the Binding Star at the top of the Queen’s palace, energy arched from the crook of Cildhureen into the Shadow Emerald that caused an explosion of light. Since then, the gem has gone black, with only a faint green light pulsing within. The gem has since been returned to Warden Corsei.