From publisher blurb:
The Mysteries of Arcane Magic
The Arcanaflow is said to be the elemental force behind the spells and magical items crafted and wielded by Humanity. Other races employ arcane magic with less skill or precision. Magical discipline is one edge that kept humans in the battle during the Harrowing.
This follow-up "Supplement III" for the Avremier old-school edition offers:
Rules and details for the Arcanaflow, and for the spellcasting class known as the Flowcaster.
A new, swashbuckling, sub-class of magic-user - the Spellfencer.
Details for running a Flowcaster in the Avremier setting.
Guidelines and specifics for arcane spellcasters among the non-human races.
More than 20 new arcane spells, including Cantrips and Arcanaflow spells.
Over 40 new and variant monsters, including the tragic, shapechanging Arcanthrope and the dimensional scavengers known as Dimmer Goblins.
A number of magic-specific items, as well as some of the singular Artifacts of Avremier. Tread unseen paths using the Dimension Doorknob, or make your move in an ancient and deadly game with Kiol's Besieger.
A look at the planetary system surrounding the central world of Avremier.
Glimpses into the near and far planes of existence beyond the physical borders of Avremier Space.