Ghast

"At least they keep their eerie red eyes shut. Until the Ghast learns you're around, of course."

- Tom Stone

Ghasts are huge, floating, white hostile mobs that live in The Nether and shoot explosive fireballs at the player. They are the second largest mobs that naturally spawn in the game, the largest being the ender dragon.

Spawning
To spawn naturally, ghasts require a solid block below them and 5×4×5 free space in order to spawn, and spawn only in the Nether, in any light level. In a single chunk only one ghast can spawn at once, although due to pack spawning the game tries to spawn up to four entities.

Ghasts do not spawn in nether fortresses.

Drops
. Looting increases the maximum ghast tears dropped by one per level, for a maximum of 4 ghast tears with Looting III. . Looting increases the maximum gunpowder dropped by one per level, for a maximum of 5 gunpowder with Looting III.
 * 5 experience points when killed by the player.

Behavior
Ghasts float around the Nether with their eyes and mouth closed and periodically make sounds that sound like moaning/crying, opening their eyes or mouth when attacking. They emit a loud screech when attacking the player and scream loudly when taking damage. The sounds that ghasts make have a minimum intensity regardless of their distance, meaning that they can sound closer than they actually are. They have a size of 4×4×4 blocks, as well as 9 tentacles about the size of a player, although longer and skinnier. However, the tentacles are not part of the ghast's hitbox.

Ghasts have a search range of 100 blocks, an explosive attack and mobility. Unlike most other aggressive mobs, the ghast does not have a pursuit mode - it does not attempt to draw closer to the player when at long range (and likewise is not particularly likely to float away). Ghasts can cause other mobs to attack it, but the ghast never targets other mobs; it targets only the player. When the player comes within 16 blocks, it opens fire, strafing left and right, and attempts to gain altitude. A ghast flees when hit in Creative.

Ghasts require a line of sight to the player before firing. Any sold blocks (including transparent blocks) can interfere with the line of sight.

If the player is able to fly inside an aggressive ghast, it may die of shooting fireballs at itself. They are also careless about being hurt by blasts from short-range shots.

Data values
Ghasts have entity data associated with them that contain various properties of the mob.

Ghast fireball
The ghast's fireball attack has a straight trajectory unaffected by gravity and a theoretically infinite range, although it disappears after 1 minute. Fireballs do not track the player once fired, are slow, and can be deflected if the player hits them with a projectile, fishing lure or melee attack. At close range, it is one of the most powerful mob attacks in Minecraft, fourth only to the explosion of a creeper, the melee attack of an iron golem, and the explosion of a wither. A direct hit deals projectile damage from the impact, and up to, , or  explosion damage from the blast, depending on difficulty. When two ghast fireballs collide, one is deflected to a random direction while the other explodes upon impact. Blocks are also set on fire by the explosion. If a ghast is killed, fireballs launched by that ghast disappear. A fireball deals 1,000 damage (500 hearts) to a ghast if the fireball was rebounded by a player.

The minimum blast resistance required to absorb all blast force of the ghast's fireballs is 20.17 (about the equivalent of a cobweb). Ghast fireballs therefore cannot damage cobblestone, which has a blast resistance of 30.

Entity data
Ghast fireballs are also entities which have associated entity data.

Trivia

 * The player can go inside of a ghast by falling through the top of it or flying up underneath it. If the player stands on top of the head, the player see inside of it.
 * If a ghast is trapped in a 1-thick cube, it shoots fireballs through the cube. This is because all mobs that shoot spawn the projectile one block in front of it to prevent the projectile from hitting the mob.
 * On rare occasions, a ghast spawns in such a way as to see through blocks (usually trapped on all sides in a tight area). When this happens and the ghast has "line of sight" through those blocks, it launches a fireball in the player's direction.
 * Ghasts can be killed in one shot by any bow with at least Power I, if you charge the bow fully.
 * C418 revealed in an AMA on Reddit that ghast sounds are taken from his pet cat, which he makes when disturbed while sleeping.
 * Two ghasts are featured in the LEGO set "Minecraft Micro World - The Nether", along with a Zombie Pigman.
 * Iron golems do not fight ghasts unless they are very close to them, even in this case it's rare.
 * When killed with its own fireball, the ghast turns orange rather than red. This is because the ghast is set on fire.
 * Splash potions affect ghasts only when hitting them on their lower half.
 * Despite not having visible feet, ghasts are still capable of making footstep sounds.
 * In snapshots 13w02a (for Java Edition 1.5), and 13w24a (for Java Edition 1.6.1) the fireball texture was replaced with a diamond helmet, and an end portal frame , respectively.
 * Ghasts are the only non-undead mob that withers are not hostile toward.