From publisher blurb:
Strange and Exotic Oni
Introduced in the Pathfinder Bestiary 3, oni are a race of evil outsiders inspired by eastern mythology. In Pathfinder, each oni is associated with a particular race of humanoid creature, and many of them are based on giants. By now, a wide variety of humanoid races have had oni made in their image, each oni using the original race as a starting point and expanding or building upon it to create a new and exciting foe, but there are still some humanoid races that have been left behind and forgotten. This is particularly a shame, because some of the races left behind are those that could make the most interesting oni.
This book contains three new oni: the shikoru (CR 10), based on the cyclops, the tororu (CR 10), patterned after the troll, and the waste yai (CR 16), made in the image of the ash giant. The shikoru can fire beams of energy from its single massive eye to burn its foes to a crisp, and can twist and distort fate, turning a roll into the opposite of what it actually was. The tororu, by contrast, can rend foes asunder with its deadly frenzied strike, and in times of dire need, can call upon its regeneration burst to increase its healing power immensely for a short time. Finally, the waste yai spreads a particularly virulent and deadly disease that causes its victims to rise as zombies, can control vermin, and has a nasty debilitating gut strike.
Whether you want to round out your cast of oni for an oriental-themed campaign, or are just looking for new and exciting takes on some classic giants, you'll find what you're looking for in these unusual oni.