From publisher blurb:
Harness a New and Original Source of Magical Power
Drawn from the ambient life energy that fills the multiverse, incarnum is the essence of all creatures. Incarnum flows as a deep blue, radiant mist, and those with the knowledge to harness this energy can shape it into objects of great power, called soulmelds. Using soulmelds crafted from raw incarnum, an adventurer opens up new avenues of ability never available before.
In the tradition of the Expanded Psionics Handbook, the Magic of Incarnum game supplement presents an alternative to conventional magic that grants access to a new source of power. Characters of all classes can experience incarnum through feats, spells, psionic powers, and prestige classes, while incarnum-wielding standard classes such as the incarnate and the soulborn allow players to take full advantage of incarnum’s amazing properties. The Magic of Incarnum game supplement includes a wealth of options and advice about incorporating this new power source into ongoing or brand-new campaigns.