False Object. If the library is motionless at the start of combat, it has advantage on its initiative roll. Moreover, if a creature hasn't observed the library move or act, that creature must succeed on a DC 15 Wisdom (Perception) check to discern that the library is animate.
Multiattack. The library makes two attacks.
Chained Book. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit:6 (1d8 + 2) bludgeoning damage, and if the target is a creature, it is grappled (escape DC 12).
The three shelves are filled with books bound in iron covers, which are attached to chains that secure them to the shelves—a chained library. The reading desk is used to support the chained books while they are being read.