Giant

Giants are over-sized mobs that look like zombies. They currently have no purpose other than decoration.

Drops
Giants drop 5 experience when killed.

Spawning
Giants do not spawn naturally, as they require a light level greater than 11 and less than 8. This effectivly makes it impossible to make them appear naturally

.

Commands
Giants can be spawned using commands such as.

Mods
By editing the code to mimic normal mobs or by installing a mod, one can make it so giants spawn naturally in the world.

Behavior
Giants are hostile, living mobs. They are twelve blocks tall and use a six times enlarged zombie model. Giants are living mobs, despite having the appearance of being undead.

Giants use to act like any normal hostile mob - they'd walk towards the player (or any mob that had attacked them) until they were touching them. However, the Giant can't "touch" anything unless it's standing on top of it, making it hard for them to do combat against opponents like Iron Golems or the Wither.

As of 1.8, Giants no long do anything, and, upon being summoned, will face south and stay that way, not even moving or turning their head. Not even hitting them will cause a response, only just knocking them back like any other mob.

Giants are in the Xbox 360 Edition, although they require external modifications for their egg to be placed in the player's inventory.

Trivia

 * Since giants need to have a light level both less than 8 and greater than 11 to spawn, they don't spawn from monster spawners. However, this spawn condition can be bypassed with a custom spawner, if it attempts to spawn an entity with valid spawn conditions riding a giant.
 * If you name a giant using a name tag, its name will appear inside its head.
 * If a Giant stands in a liquid, it can't move.
 * Giants for the longest time had the largest health pool of all the mobs. While they no longer claim that title, they are still the tallest mob in vanilla Minecraft, standing at an astounding 12 blocks tall. They also claim the title of having the most dangerous attack in the game, beaten only by a charged creeper's explosion.
 * Giants share the exact same model as the zombie. This means that changes made to the zombie model change the Giant's as well.
 * Notch removed the Giants spawning capabilities because "they are too overpowered".
 * If a Giant is riding a minecart, it hovers way above it.
 * If a mob is riding a Giant, unless it's a very large slime or magma cube, a ghast or the ender dragon, it is completely hidden from view by the Giant's head.

Gallery
Riese Gigante Géant Óriás ジャイアント Reus Gigant Гигант 巨人