From the back cover:
Come to a land of hills and shadow, where faeries evil and benign daily touch the lives of the inhabitants. Here, near-immortal magicians change throughout the centuries into hideous monsters, and monoliths tell of ancient battles in tongues spoken only by a few shadowy magi.
Explore a covenant housed in a faerie mound with sentient walls, or one of the Saxon renegades living in caves. Meet the strange, rough wizards known as the gruagachan, and arrive at a showdown with the venerable and wicked Damhan-allaidh, instigator, and eldest survivor through long ages, of the war that spawned the House Ex Miscellanea.
Lion of the North: The Loch Leglean Tribunal is the third tribunal book for Ars Magica(TM). Here is everything you need to play individual stories or entire sagas set in Mythic Scotland. You'll find extensive historical background on the region, as well as new creatures, rules for new magi, and much more.