From publisher blurb:
This book contains 117 monsters from the award-winning Trilemma Adventures series, with stats for Year Zero Engine fantasy role-playing games. Inside are beasts of the wood, alien aberrations, people of the underworld, celestial horrors, demonic incursions, and ghostly remnants of ages past. Tons of entries to surprise your players and enrich your campaign. Use them along with the Compendium, or in adventures of your own.
Many of the entries have fully detailed attack tables, so you'll always have an interesting option during combat.
In addition to the monsters, there are also:
talents for seven new playable kin
encounter tables for eleven terrain types, making it easy to find an appropriate monster in any campaign
fire and burns critical tables
six detailed magical items, from the deadly Axe of the Kinslayer to the mysterious Wizard Flowers