Anvils are Shaman items which can be used to weigh down objects and prevent them from moving. Because of its weight, it is very difficult for mice to shift Anvils, which can prevent trolls from damaging contraptions. However, the Anvil can also be used by troll Shamans to destroy bridges etc.
One of the most common use of Anvils to is to create an Anvil God by attaching multiple anvils to each other using the rotating anchor. Another common use is to balance platforms, and airships, or to launch mice using a catapult. Troll Shamans will often drop anvils on players who are attempting to scale walls.
Shamans can use anvils as stepping stones or stairs to help mice get around certain obstacles.
Anvils can also be used, in a combination with a plank and small box, to kill mice.