Staff of Teleportation

Teleports the Hero to the targeted allied land unit of structure. Has a casting time of 3 seconds.

Source
Can be bought from Goblin Merchants. Maiev can find one in Wrath of the Betrayer, chapter 4 of the Frozen Throne sentinels campaign, Terror of the Tides. She can't sell it, and it will disappear at the end of the chapter.