Snow Golem

Snow Golems are the game's first "utility mob", which Notch defines as any player-created mob. They are by nature friendly to their creator. Snow Golems are created using pumpkins and snow blocks, and will throw snowballs at enemy mobs. As Snow Golems move, they leave a trail of snow on the ground, except in Plains, Ocean, Desert and Swamp biomes, and the Nether. If a Snow Golem walks over a mushroom, the mushroom will be destroyed and dropped as an item. Snow Golems do not take fall damage. Once killed, the Snow Golem will drop a maximum of 15 snowballs.

Creation
To create a Snow Golem, the player must vertically stack two snow blocks on the ground and then place a pumpkin on top of them. A Jack-O-Lantern can also be used instead of a pumpkin, although there is no effect on snow golem's appearance. They will die very quickly if created in a Jungle or Desert biome, or the Nether, even if it is snowing in the biome.

Players should be aware that Snow Golems cannot be made on the crafting table, and are only created when the pumpkin is placed last. Pistons cannot create Snow Golems, as they cannot push pumpkin blocks. Endermen are capable of creating Snow Golems by placing the necessary blocks, although this is an extremely rare event because they do not do so purposefully.

Behavior
Snow Golems throw snowballs at hostile mobs up to 10 blocks away, provoking them. This gives them a humorous, yet an almost suicidal nature, as the thrown snowballs do not do any damage, except to Blazes. They will attempt to move towards hostile mobs, forming a wall, and will even open and go through doors and trapdoors to reach them. Snow Golems attract enemies and do not follow the player, making them useful for luring enemies into traps. Snow Golems have good pathing skills, and will not jump off cliffs or into lava. If a Snow Golem is lit on fire, it will speed up and move toward a water source. Snow golems "melt" (take damage) in Deserts, Jungles, the Nether, and when in contact with rain or water.

Defense
A Snow Golem's primary purpose is to defend the player from mobs. Four Snow Golems throw snowballs quickly enough to continuously push a Zombie back. Due to their small health, however, players are advised to use many all at once. Snow Golems will attack Zombie Pigmen regardless of whether or not they attacked the player, thus making the whole horde attack them. Snow Golems never attack hostile Wolves, Slimes, Magma Cubes or Ghasts.

Here are a few examples of efficient ways to defend yourself and your valuables:

A horde of Snow Golems kept between two lines of fence provides a wall that constantly pushes back mobs at a distance, and in an emergency, they can be released to push back approaching enemies. Another way is to place them into guard towers, shielding them from damage. To create such a guard tower, make a small 3x3, 1-4 block high tower. Surround the top with fencing and create a Snow Golem in the center.

Farming
Because Snow Golems leave a constant trail of snow as they move (except in Plains, Swamps, Deserts, Beaches, Jungles, Mushroom Biomes, and the Nether), it is possible to farm that snow. However, because of their habit of attacking hostile mobs, it would be wise to ensure the Snow Golem is in an enclosed, safe place in the beginning. The simplest method is to create a 1x1 hole that is 2 blocks deep, and to put both the player and the Snow Golem in. Then the player would look straight down and farm the snow that is produced. This creates an unlimited amount of snow in the shortest time possible, because the instant the snow breaks, another one forms in its place. A shovel must be used to collect the snow, or it simply disappears. It drops snowballs, and four snowballs can be crafted into one snow block.

History
Snow Golems were first mentioned by Notch on September 21, 2011 and were slated to appear in Beta 1.9.

In The Story of Mojang, Notch briefly mentioned adding "snowmen that throw snowballs."

Notch originally planned to call this mob Snowmen. However, very soon after revealing the name, Reddit user Cuttleman stated he would call them "Snow Golems," a name Notch approved of and made official.

During the Beta release candidates, Snow Golems would attack players holding wheat. This is now fixed.

When breeding was released in 1.9pre2, Snow Golems could breed as well. This was a bug and was fixed in 1.9pre3.

As of Snapshot 12w06a, Snow Golems have a new path-finding AI and will form a wall to attack mobs.

As of Snapshots 12w07a/b, Snow Golems take damage in Deserts, Jungles, the Nether, and when in contact with rain and water.

Bugs

 * Snow Golems do not leave snow trails in Mushroom Biomes, near Bedrock, nor on Ice or glass.
 * In SMP, Snow Golems do not make sounds when throwing snowballs.
 * In SMP, placing the two Snow blocks with a Sign on the bottom one, then placing the pumpkin on top will result in the pumpkin being cloned, but the Snow Golem still being spawned. This can be used to make infinite Snow Golems, by using the snow from their trail.

Trivia

 * Although Snow Golems will attack most hostile mobs, they will only agitate Skeletons, Spiders, Cave Spiders, Zombie Pigmen, and Blazes. Endermen simply teleport away.
 * Snow Golems wear their Pumpkin as a helmet just like the Player does. Their actual Snowman-type head is hidden beneath it. If the player occupies the same space as a Snow Golem, the Snow Golem's Pumpkin helmet will be seen through, revealing their face.
 * The throwing sound is actually the Bow firing sound, even though Snowballs have their own throwing sound.
 * Snow Golems can only be crafted by placing a pumpkin on top of two snow blocks; placing the pumpkin then snow underneath will produce no Snow Golem.
 * If trapped underwater, Snow Golems can drown.
 * Snow Golems do not create ice when moving onto a water block.
 * Snow Golems cannot be made by pistons because the code for generating Snow Golems are found in the Pumpkins "OnBlockPlace" (When placed by a player) event, Also pumpkins will be dropped as an entity when pushed by a piston.
 * Using a texture editor with the pumpkin texture invisible, the true Snow Golem's face can be seen.
 * Snow Golems are known as SnowMan in the game files.
 * When constructing a Snow Golem, it will be 3 blocks high, but when it activates it becomes only 2 blocks high.
 * Snow Golems will take damage during rainfall.
 * Snow Golems, Villagers, and Squid are the only mobs that do not make any sound (except when Snow Golems are attacking).
 * It was once possible to breed Snow Golems, but the feature was removed after their release.
 * Since the damage Snow Golems take in hot biomes is fire damage, a splash potion of Fire Resistance thrown immediately after the creation of one will make it survive. With redstone dust, this means around six minutes. In the Nether it will prevent damage from fire, lava and Blaze fireballs, but not Blaze contact.