Minecraft Dungeons:Phantom

The Phantom is an hostile mob that appears at Night when a player dies in multiplayer.

Spawning
The phantom can only be summoned when a player dies in multiplayer. Unlike their default counterparts, the phantom is immune to all attacks and can only be stopped by reviving all defeated players and ending the night status.

Sometimes, in levels such as the Pumpkin Pastures, the player can see their shadows flying around in circles around them.

Behavior
Unlike their default counterparts, The Phantom swoop to player vertically instead of horizontally, but will first start with one player then groups of them will swoop other players until all players are killed, or until the night ends due to all killed players being revived. The first bite deals 8% of the player's HP, 10% for the 2nd bite, 12% for the 3rd, and so on and the damage keeps increasing over time.

Trivia

 * The attack and flying behavior of phantoms in Dungeons is similar various species of hawks in reality instead of the original game, which used the Ender dragon's behavior.
 * The phantom is the first and only mob that is immune to all attacks.