Universal Horizons Player's Handbook

Publisher's blurb:

Players learn the [Universal Horizons] system quickly, within ten minutes. The combat, expertise, and spell system create an atmosphere for advanced players to be challenged. Moreover, the Hero transfers to other genres seamlessly. Thus multiple world campaigns, traveling to other genres, and time-shifting adventures called paradoxals happen with ease.
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A must to run the system, this book explains the resources, abilities, skills, and rewards, and how these things apply to the game.