a wailing banshee  

In the Plane of Hate: (no data)

In the Plane of Nightmare: (no data)

In the Theater of Blood: (no data)

In the Cooling Chambers: (no data)

In the Convorteum: Part of "The First Creation" event (see this quest entry for event information and loot).

In Tempest Temple: (no data)

In the Caverns of Endless Song: (no data)