There are some who take on the mantle of adventurer for the gold and the glory. Others have the dubious title thrust upon them through circumstance or fate. Then there are some who seek out the adventurous life for the sheer sake of knowledge and discovery of the unknown. Enter the Deductionist. The Deductionist is an original base class which will find a niche in almost any adventuring group. Highly skilled, and incredibly perceptive, the Deductionist overcomes his adversaries with reason, rather than sheer brawn. The Deductionist is a fun class capable of a wide array of abilities and their reason powers grant them almost supernatural abilities. Each Deductionist is a master of a chosen discipline of knowledge, with almost sage-like ability. With over 38 deductive abilities to overcome their foes, no single Deductionist will be the same. Confound your opponents with the truth, avoid their blows with danger sense, exploit their weaknesses and even learn mystic abilities. This sourcebook also includes 17 new feats, 13 new pieces of equipment and three new archetypes: The Operative, The Eldritch Inspector and the Shadowed Avenger. Knowledge is power, and it is in your hands now.