An elemental can come in various sizes or forms: they can be very small, such as lizards, or big and bloated on magic, like wyverns, dragons, and sea serpents; they can also have human forms.
Rogue elementals are usually put down, but some are subdued and bound by mages for service such as Skelmis. Controlling and using an elemental—to perform magical tasks, for instance—takes less energy and is easier for a mage than performing magic itself.
Several elementals can be found living in the caves of the Magisterium. Some are deceitful or outright scary and should be approached and trusted with caution.