Phantom

"This manta-ray-like monster is a flying creature that spawns at high altitudes. It is attracted to insomnia, and will find players who haven't slept for many days. It will swoop down in groups and bite your flesh."

- Jens Bergensten

Phantoms (previously known as Mob B or The Monster of the Night Skies) are flying common hostile mobs that attack players who haven't slept in a while.

Spawning
Phantoms spawn in the Overworld after the player has not slept for at least 3 days.

For a Phantom to successfully spawn, the following criteria must be met: Once these requirements have been met, the game will attempt to spawn a pack of 1–4 Phantoms 20–34 blocks above the player with a taxicab distance of up to 9 blocks from the exact spot every 1200-1400 ticks (1–2 minutes). The chance of a successful spawn increases with every night the player hasn't slept, calculated via $x-3⁄x$ with x being the amount of nights the player hasn't slept and therefore starting at a $1⁄4$ chance on the fourth night for every attempt.
 * The player must not have slept for at least 3 days (an hour of game time)
 * It must be night time
 * The player must be above sea level and not have a block above its head which blocks light in any way (e. g. leaves won't work as they have a light opacity of 2, but glass will work as its light opacity is 0)

With a $1⁄4$ chance on day 4, $2⁄5$ on day 5, $3⁄6$ on day 6 etc (specifically, random.nextInt(ticksSinceLastSlept) >= 72000) Phantoms are counted towards the hostile mob cap, but don't respect it when spawning. The spawning mechanic is based on the location of players in the world, not by randomly choosing a block near the players like regular mob spawning.

Drops
Phantoms will drop 1–4 leather when killed, which can be increased with the Looting enchantment. However, this will likely change.

Behavior


When idle, phantoms will fly around in a circle at a constant y-elevation, leaving a trail of gray smoke while doing so. They have a quite large search radius, and will occasionally either swoop down or up quickly to attack their victim. If stopped or hurt during this action, the phantom will retreat back to its original elevation. When idle over water, the phantom will sometimes swoop into the water and will die as it is not pushed back up.

In water, the player is at a large disadvantage to the phantom, as the phantom's motion is not affected by water.

Trivia

 * Phantoms have a Size tag, which determines the size of the mob.
 * The phantom was added into the game as as result of winning the Minecon Earth mob Twitter poll as "Mob B".
 * Phantoms are currently the fastest non-boss mob in the game, traveling at speeds of up to 20.83 blocks per second.