A smouldering fever grass is formed when a tinderbox has been used on a fever grass in the player's inventory with the right hand weapon slot empty. The fever grass disappears and appears as a smouldering fever grass in the right hand weapons slot (Examine: A slowly-burning, acrid-smelling fever grass.) If dropped, it turns into ashes and the message The smouldering fever grass disintegrates to ashes. is shown. If the right hand slot is full: You need to have your right hand free to keep the fever grass burning. Fever Grass, as well as Lavender and Tansymum, cannot be lit outside of Oo'glog.