From publisher blurb:
Colours of Magic: Green Fifth Edition Update
A Spectrum Shift: Chromatic Arcana Product
In some worlds, Magic may not be seen as a force in and of itself. In some philosophies, magic can not be classed by types of effect, like Evocation, Illusion or Abjuration. Instead, it might be seen as a result of fundamental aspects of arcane metaphysics.
One such theory holds that all magic is a result of the principles of Colour.
Green is the colour of Animals, Plants, Water and Air. But the environment is more than its parts, it is systems of dynamic ecology, and contains forces that destroy as well as re-grow.
Those that devote themselves to understanding the Green are able to manipulate the Environment, Command Air and Water to act as they will, and even to draw upon the characteristics of natural things to mimic or manipulate them. Druids tap into this force through their association with the wild, but a cleric might beleive in its power in a more objective way, a sorcerer might be a living incarnation of biological diversity, and a wizard might study it clinically, and learn how to use it for broader purpose.
Included in this product:
3 new Class options, one for each of Cleric (Elementalist), Sorcerer (Symbiont) and Wizard (Animist)
a reclassification of one eleventh of the spells of the players handbook