Iron Golem

Iron Golems are large, 3 block-high, strong utility mobs. Their main purpose is to defend Villagers in NPC Villages from hostile mobs.

Creation
Iron Golems will spawn in NPC Villages naturally, provided there are 15 villagers. It does not even have to be a naturally generated Village, as long as there are 15 villagers and a house, an Iron Golem will spawn.

The player may create them using blocks in a similar fashion to Snow Golems. To do so, the player must place 4 blocks of iron in a short T-shape, and then place a pumpkin on top. This is equivalent to 36 iron ingots, making creation somewhat of a task. They will always spawn facing south.

Behavior
Iron Golems roam villages rather slowly. When provoked, Iron Golems will move toward their target at a faster rate, swinging their arms up violently once in range to attack. This does 3½ to 10 hearts damage to their target. They can take damage from lava, fire, poison, and drowning. They do not take fall damage. Upon death, Iron Golems drop three to five iron ingots, and sometimes one or two roses.

Iron Golems are able to hold roses and give them to Villagers and Villager children, symbolizing the friendly relationship between Iron Golems and the Villagers.

Iron Golems will attack all hostile and neutral mobs if any come within their sight, except Creepers, Slimes, Magma Cubes, Wolves, and Ghasts. Iron Golems do not attack Creepers, likely due to a Creepers destructive nature which may destroy sections of the village. They will attack the player if the player attacks it first, or if the player attacks a Villager (only in Survival Mode). The Iron Golem does not have to directly see the player attacking a Villager to become hostile toward the player. They do not despawn if the difficulty is switched to peaceful and will continue to attack the player.

Iron Golems have a larger than normal attack range, this causes them to be able to attack through a solid 1 block thick wall, even without line of sight to the target.

Iron Golem will ignore everything if it's riding minecart, even if target is in attack range (Bug?)

It is possible for Iron Golems to accidentally attack one another, although this will deal no damage nor provoke them against each other. If an Iron Golem generated as part of a NPC Village is killed, another will eventually spawn to take its place.

Defense
An Iron Golem's primary purpose is to defend NPC Villages from Zombie attacks. When attacking, they swing their arms as if tossing the enemy. The enemies are thrown up into the air and normally are killed in one or two attacks. Player usage might involve a large fenced off area inhabited by them to prevent wandering off, although such control of the area could be accomplished in more simple ways.

Farming
Although difficult to kill, farming Iron from them using respawning ones from NPC Villages is possible. Their unusually high health and heavy damage make melee combat impractical. Since Iron Golems cannot swim, it is possible to lure them into a 3-block deep pool of water, where they will eventually drown. Another way is to turn them hostile, retreat to a safe place while a large pack of tamed wolves attack the golem. You can also kill them by placing netherrack and lighting it on fire which shall eventually kill them.

History
Iron Golems were first introduced in Snapshot 12w08a.

Bugs

 * When creating Iron Golems in a 3 tall area (the Pumpkin directly against the ceiling), the block directly above the Iron Golem will break.
 * If an Iron Golem dies in lava, the block(s) of lava that it died in will be removed and the lava will not flow into those blocks even when they are filled with another block and it is mined out again.
 * If an Iron Golem attacks a group of Zombie Pigmen, the whole group won't turn hostile towards the Golem, only the one attacked.
 * After attacking an Iron Golem and making it aggressive, logging out of the world then back in will make the Iron Golem peaceful again.
 * If an Iron Golem falls into a 3x3 pit of water, it will spin rapidly.
 * If you attack an Iron Golem, run away, and return, the Iron Golem will turn Passive again.(Only tested in creative yet)

Trivia

 * As the population of a village increases, more Golems will naturally spawn.
 * Castleintheskyrobot.png Iron Golems holding out roses to Villager children is a reference to the ancient robots in the Japanese anime movie Laputa: Castle in the Sky, as is the fact that the Golems are covered in vines.
 * When Villager children notice the rose in its hand, they will slowly approach, and take the flower eventually.
 * As with Snow Golems, the pumpkin must be placed last.
 * Also as with Snow Golems, there is no Spawn Egg for this mob. This is because the player can create them through other means.
 * It is implied by their looks and natural generation location that these were created by Villagers to defend them.
 * Unlike other mobs (apart from the magma cube), Iron Golems will sink to the bottom of any liquid.
 * Iron Golems will avoid water whenever possible.
 * When created, a snow particle effect will display.
 * There is no maximum number of Iron Golems per village.
 * Despite being crafted with a pumpkin head like a Snow Golem, the Iron Golem's head is made of iron instead of being a pumpkin, possibly being covered with crafted iron.
 * Iron golems wobble as they walk, unique to other mobs which are completely upright when walking.
 * Tamed Wolves will not be attacked by the Iron Golems if they are focused on the player.
 * Iron Golems have the second highest health points in the game, the first being the Enderdragon boss.