From the back of the book:
Expand the horizons of your RuneQuest campaign with the exotic creatures in this book. All new, they can be used to create numerous interesting encounters. This book contains 99 new monsters from a variety of sources, presented in the clear and concise format of RuneQuest, complete with illustrations. This is the first of our Gateway products, which are designed to aid the referee who desires to run a RuneQuest campaign without the restrictions of the limited flora and fauna of Glorantha.
GIANT ANTHROPODS - This section includes your favorite insects in human size forms such as giant ants, spiders, or wasps capable of carrying a rider.
LEGENDARY BEINGS - Provides monsters from terrestrial mythos, such as the hydra, gorgon, lamia, or sphinx.
CELTIC HORRORS - Contains terrifying creations of the Gaelic mind. These include kelpies, voughs, and more.
H. P. LOVECRAFT CREATIONS - These are the otherworld nightmares of Lovecraftian mythos such as the rmi-go, nightgaunt, or shoggoth.
NATURAL ANIMALS - This section fills the more obvious omissions of íhe original RuneQuest rules by including stats on frightening carnivores like lions or bears, and the smaller animals useful as familiars, such as owls or monkeys.
DINOSAURS - Here are the giant prehistoric creatures... from the bulky sauropods that are likely to crush an adventuring party by accident to the terrifying carnosaurs which should make any batch of Rune level characters turn and run.
MISCELLANEOUS TYPES - These include the whimsical creations of Lewis Carroll to the fatal anthropophage from a well-known science fiction movie. Complete statistics are provided, just roll them up and see the players try to figure out what they're up against!