Iron Golem

Iron Golems are a village's self-defense mechanism introduced in 12w08a.

Creation
Iron Golems can spawn naturally in villages, or be built with blocks, similar to a Snow Golem. It takes 4 Blocks of Iron to build an Iron Golem, which is equivalent to 36 Iron Ingots. Iron Golems always spawn facing south.

Behavior
Iron Golems roam villages and move slowly with no intent of attacking anything. When provoked, Iron Golems will move faster toward their target, swing their arms violently at whatever is attacking it, and instantly kill it (assuming it has as much or less HP than the player). This is especially useful for killing of hordes of Zombies, as was the reason for creating them. They will attack Endermen, zombie pigmen, blazes, silverfish, skeletons, spiders, cave spiders and zombies if any of them is within their sight. They do not despawn if switched to peaceful and will continue to attack the player (if provoked earlier by hitting him). Golems do not attack creepers (maybe because they would explode when it attacks them, destroying the village over time) or slimes (Bug?)

Upon death, Iron Golems respawn.

Iron Golems take damage from lava, fire and drowning. They do not take fall damage.

Defense
An Iron Golem's primary purpose is to defend villagers from zombie attacks. When attacking, they swing their arms as if tossing the enemy. The enemies are thrown up into the air and killed.

History
Iron Golems were introduced in 12w08a.

Bugs

 * Iron Golems do not attack Creepers (may not be a bug, as wolves also don't attack them), Magma Cubes, Ghasts or Slimes.
 * Sometimes an Iron Golem's texture is pure white or invisible.

Trivia

 * Iron Golems have a nose resembling that of a Villager.
 * At times it will hold out a Rose to baby Villagers. This may be a reference to the movie Laputa: Castle in the Sky.
 * When babies notice the Rose in its hand, they watch the Iron Golem until one of them approach shyly and take the flower away (or eat it ?).
 * Just like for the Snow Golems, the pumpkin must be placed last.
 * The is no Spawn Egg for iron golem because they can be created by the player.
 * Since Iron Golems look like Villagers and respawn in NPC Villages, they must be created by Villagers to defend themselves against hostile mobs and particularly Zombies.