Druid

Druids are nature mages. They study mana and its relation with the material world, and seek to maintain harmony between reality and the astral realm. Like wizards, druids learn to harness magic under their own power, but unlike wizards, druids do so intuitively rather than academically. This results in druids having a smaller number of spells to choose from than wizards, but they gain more insight into the world.
Many druids form close bonds with animals, and can call upon them in times of need. A few more can even shapeshift into animals, to better understand the world in ways only beasts can. Their reverence for nature means all druids, and indeed all nature mages in general, are expected to be Ecophiles and Philozoic, meaning they must love and care for the environment and wildlife. Those who break these tenets are cast out, ruthlessly hunted as renegades.
All druids are expected to belong to one of three druidic circles. Those who are not within one, or who are cast out, are declared hedge mages.

Druidic Circles

Circle of Earthen Divinity: Druids of a Circle of Earthen Divinity have devoted themselves to a specific nature god, and act somewhat like clerics for their god's faithful. These druids are guided on their journey to gain nature magic and are held to a higher standard. Earthen Circle druids gain a primary and secondary divine domain, including its domain benedictions, and additional spells. In exchange, not only must they remain Ecophiles and Philozoic, but also Devout, and aligned with their god's disposition requirements.

Circle of Halcyon: The least demanding circle, it is a part of the Arcanists' League, more concerned with policing magic than moderating the natural world. Halcyon druids can only select a secondary divine domain but are only held to the base standards all nature mages must abide by.

Circle of Mana: Circle of Mana druids are concerned with the balance between reality and the astral, and do not necessarily care about the state of the natural world. While still expected to be Philozoic and an Ecophile, these druids are able also expected to be somewhat moderate in their temperament. Mana druids must remain Neutral on at least one alignment axis. They may select a primary domain and its benedictions, but no secondary domain.

Renegade Druids: Druids who do not fall into one of the above circles are illegal hedge mages. Such druids are not held to any standard but will be hunted relentlessly for their betrayal.

Classes

Greenkeepers, the default druid and the only one that is guaranteed a pet
Cosmic Tenders (Cyclopes only), robotic druids that cannot wild shape but have more combat training, and must serve a Circle of Mana
Elementalists, psychic druids who add mentalist spells to their repertoire, but are more strictly policed
Naturalists, druids with danseur and monk training, they forsake wild shapes but can fight naked and unarmed
Primalists, savage druids who harness barbarian rage while in wild shape

Recommended Prestige Classes

Archdruids
Chosen Ones
Dragon Disciples
Hag Matriarchs
Living Legends
Troll Patriarchs
Zoomorph Exarchs