Shulker

The Shulker is an upcoming hostile mob added in 1.9. It dwells in end cities. It hides in its shell to blend in with surrounding purpur blocks.

Spawning
Shulkers spawn in end cities, which are located on the outer islands of the End. They often spawn on the walls of the dungeon.

Appearance
The shell of the mob looks similar to a purpur block, blending in relatively easily to its End city surroundings. Inside the shell of the mob lies its "core," a small yellow head.

Behavior
Shulkers lay dormant in their block, sometimes opening their block to peer outside. When the player comes within a certain range (or if provoked by other mobs), it will attack. When attacking, shulkers open up (similar to magma cubes) and shoot bullets which only move along the X, Y, or Z axis. The projectiles can be destroyed by attacking them. If the player gets hit by one, it causes of damage and inflicts the levitation status effect.

Shulkers sometimes teleport when attacked. They also teleport when spawned on top of a piston, or when pushed into a block by a piston. They will also teleport when spawned onto a transparent block, including slabs and stairs. They seem to teleport with a range of about 8 blocks. If there are no available spaces in this range, then they will not teleport at all.

When its shell is closed, it is invulnerable to arrows.

If a shulker is put in a minecart, its form will flicker across the screen from where the minecart is to where the shulker was before it was picked up by the minecart. When the minecart is destroyed, it will teleport back to where it was before the minecart picked the shulker up.

Trivia

 * The name shulker is short for "Shell Lurker".
 * The block that shulkers hide in is not usable or obtainable.
 * By using commands, they can be made to be part of a team to attack other teams and can be used as defense mobs. In that case, it won't attack its teammates

Gallery
Shulker Shulker