Elementals

Elementals were the purest living forms of the four basic elements—air, earth, fire, and water—as well as several other, less common elements. They were intelligent, self-aware entities that were made up of the matter of their home plane. They could be summoned to any plane of existence, except the plane of concordance to their element. For example, summoning a Fire Elemental to the Elemental Plane of Water took more magical power than mortals could conceivably wield.
Elementals were considered intelligent. Summoning and binding an Elemental required much in the way of personal power. An Elemental that sensed binding of this manner would fight the caster mentally. If the caster lost this battle of wills, the Elemental was free to wreak havoc on the plane it was summoned to. In most cases, the Elemental would slay the caster and return to its home plane.
The four main Elemental types were fire, water, earth and air. Races tied to a certain element were much more likely to summon an Elemental of that same element. Salamanders were known to have the ability to request service from Fire Elementals. The Efreeti were also known to have these agreements.