Aumry's staff of the night

The staff of the hulk was a magical staff once possessed by Aumry, Lord of Shadowdale. It was made from twisted iron and a violet geode lay at the top, held by a claw. The staff can be used once per day to summon an umber hulk to do its wielder's bidding. When used, the geode at the staff's top glows and shoots a purple beam into the ground, from which the hulk appears.