Temporary Skill

Some quests, items, or regional effects will cause you to temporarily gain a skill or skills. Some of these will have a time limit they must be used during, while others will persist as long as you have not changed zones or finished the quest they are associated with.
Any Temporary Skills will appear above the hotbars of your normal skills and any pet skills, and may be initiated with the Alt-key plus a number. So Alt-1 uses the first skill, Alt-2 the second, and so on.