Ogre Waystone

Ogre Waystones are charged stones used for the opening of Ogre Waygates. 25 of these stones can be collected to activate the gates.

Source
Ogre Waystones drop from ogre mobs across, as well as in the Bloodmaul Slag Mines dungeon and the Highmaul raid. Collecting Ogre Waystones requires the construction of a Mage Tower (Alliance) or Spirit Lodge (Horde) in the player's garrison.