So Ombric conjured a second ring of defense—a great black bear, the largest in all the Russias, whose courage and devotion were unquestioned. The bear would patrol to protect the village from anyone who might cause harm. 

Then, on the outer rim, Ombric planted a third ring—majestic oaks, the largest in the world, whose huge roots could rise up and block the advance of any who tried to enter with evil intent. Ombric had to search through seven of his most ancient journals to find just the right enchantment to accomplish that feat! 

And in case that was not enough to keep the intruders away, Ombric conjured up one more thing: a ghostly temptress with a beguiling smile. Adorned with what seemed like glittering gems, his Spirit of the Forest could lure visitors of an unkind or ignoble disposition to a particularly useful doom, turning them into stone, cursed forever to be a part of the village’s defenses.

Nicholas Saint North and the Battle of the Nightmare King Chapter 2