The Crystal Hall is an area of the Exodar. The shaman trainers can be found here, as well as a small crystal-digging mine full of Broken workers. Note that the shamans are not all draenei; there are also furbolg and broken shaman trainers around, including the most important one, Farseer Nobundo, located at the small elevated platform in the zone. The Crystal Hall also houses numerous trainers: a first aid trainer, a fishing trainer, an enchanting trainer, and a jewelcrafting trainer.
Another notable NPC in the area is Seer Skaltesh, close to the enchanting enclosure. If the player talks with him, they are given which can be consumed and gives Sapta Sight to the player for one minute. While under this spell, it is revealed that there are, in fact, numerous elementals present in the Crystal Hall.
An interesting fact is that the draenei harvest crystals in the northern portion of the hall, where Broken draenei miners use their mining picks to gather the precious gems. This part reminds one of an excavation site. The crystals are used to repair the Exodar. It is gathered that the Broken draenei, though still draenei in some regard, are treated like a lesser class; a labor and task force. It is kind of odd that a race with such an attachment to the Light treats those who were once their own people with such distaste. It is possible that the arrangement was agreed to by the Broken draenei; their bodies better suited to manual labor than the "pure" draenei.