Anvil

An Anvil is a block that uses the new item repair interface to repair, rename, and combine enchantments on items.

Usage
Anvils can be used to repair and rename items and blocks, and can be dropped like sand.

Repairing and renaming
Unlike crafting to repair items, Anvils can use materials to repair or combine two items. Anvils can both retain enchantments and expand on them. The player can also rename any item - not just tools or armor - using this method. This costs levels proportional to what is given. Simply renaming an item will cost 5 levels for a non-tool/armor item, whereas renaming and repairing an enchanted tool/armor is substantially more. As it is used, the anvil will become damaged. On its last use, taking the item will cause the GUI to close and anvil to disappear, dropping the item on the ground.

Falling anvils
If there is no block below an anvil, it will fall.

When an anvil lands on a non-solid block (like torches, rails, etc.), it will destroy that item instead of dropping itself as an item like sand, gravel, and dragon eggs do. When dropped on a pressure plate, a boat, cobwebs, a slab, a sign, a cake, a lily pad, closed trapdoor or opened fence gate, the anvil will drop as an item. When dropped on a flower pot, the flower pot is destroyed without a drop. When dropped on a head, the head is dropped as an item.

A falling anvil will also damage mobs and players. Damage amount depends on fall distance: × MAX(Distance - 2, 0). A player dying by an anvil falling on them will receive this message: "player was squashed by a falling anvil." However if a player is touched by an anvil entity, or falling anvil, no damage will result until the anvil becomes a block in the gridspace where the player is. So anvils can be shot with a TNT Cannon, and pass right through a player, and not damage him/her.

Bugs

 * Because anvils are not an eight-way symmetrical shape and Falling Sand retains a single orientation, no matter which direction an anvil was facing before it fell, it will default to a specific orientation while falling.
 * When digging with an anvil, the bottom of the top half is invisible. When it's placed, that visual bug is gone. Item frames also have a similar bug; placing an anvil will make the bottom of the top half invisible, as well as the bottom part.

Trivia

 * It takes a total of 31 iron ingots to craft an anvil.
 * Similarly to obsidian, bedrock and End Portal Frames, anvils cannot be pushed or pulled by pistons.
 * Placing down a renamed placeable item will not retain the name if the item is picked back up again.
 * The anvil has the same blast resistance as obsidian and enchantment table.
 * Anvils being affected by physics may be a reference to classic cartoons, in which anvils were used in traps that usually backfired, causing the anvil to fall onto, and severely hurt, the antagonist.
 * If you wear a helmet, the Anvil can fall from any height and you will always take health points of damage.
 * It needs iron to be crafted, but looks much darker than iron, similarly to cauldrons and it looks more like stone.
 * You cannot re-name a sword if it has 4 enchantments.