The high pitched cries of the ghasts are often the first thing you hear when you enter the Nether. These white, floating, jellyfish-like creatures can be a real pain to deal with.
Upon death, a ghast will drop 0-2 pieces of gunpowder, 0-1 ghast tear and 5 experience points worth in orbs. Due to their nature to keep their distance from players while attacking and their natural ability to float, these drops can often end up falling in lava or off of a cliff.
Ghasts will normally float gently around the Nether with their eyes closes, occasionally making high pitched sounds. These sounds have a minimum intensity, which means a ghast 100 blocks away from you will sound just as loud as a ghast 20 blocks away from you. When you’re close enough to a ghast (about 16-17 blocks), the ghast will start to shoot fireballs in your direction. When it does this, its eyes and mouth will open. Upon impact, these fireballs will explode either destroying nearby weak blocks or setting nearby netherrack on fire. So be careful not to set yourself on fire when running away, or to fall down when the floor underneath you has been destroyed.
Ghasts will always face a player when it’s close enough, even if it’s behind an obstacle. However, ghasts require line of sight to fire at you, which means you can build transparent walls or windows without being able to get struck by a ghast. Transparent blocks include leaves, glass, vines, fences, cobwebs, iron bars and even Nether portals.
The ghast will keep its distance from you and will still be able to fire at you from up to 100 blocks away.
To kill a ghast you can either shoot it with your bow or deflect its fireball back towards the ghast. To do this you can either shoot it with your bow or ‘attack’ the fireball when it gets close to you. You don’t have to hit the fireball with a sword, any item will do. Even your bare hands are strong enough to deflect a hot, explosive fireball. It’s possible to shoot it back using a bow and arrow, eggs, snowballs and even the bobber of a fishing rod.
Ghasts can spawn anywhere in the Nether, but they need a 5×5 area to spawn in. This means they can also spawn in smaller areas in which they’ll be trapped, but this doesn’t happen very often. Ghasts can only spawn on blocks, which means any transparent block, like torches, in their way will prevent them from spawning. This can be useful when you want to prevent ghasts from spawning inside a large room in your nether house.
Ghasts are immune to fire and lava, they will be set on fire if they fly through a lava stream or burning fire, but they won’t die from it.
Funnily enough, ghasts can ride minecarts, which could lead to an explosive surprise at the next stop. Unfortunately you cannot stand on ghasts, you will simply fall through them.
As mentioned, the ghasts fireball will explode on impact, destroying any weak block nearby. This means that in order to make your house blast proof you have to make use of any of the following blocks: Enchantment tables, obsidian, end stone, brick, stone brick, cobblestone, diamond blocks, gold blocks, iron blocks, jukeboxes, moss stone, nether brick, nether brick stairs, nether brick fences, stone stairs, slabs, stone, iron bars, iron doors, water or lava. Players who use commands or mods can also use monster spawners, end portal frames and bedrock.
It’s important to note that an iron door is the only safe item you can use to allow people in and out, without allowing monsters in. However, buttons, levers and pressure plates can be destroyed by the ghast’s fireball, meaning you have to find a way to prevent them from hitting the area around your door.
The explosion can also deactivate Nether portals (or activate them), so be sure to surround your portal with cobblestone if your portal is in a ghast infested area, you don’t want to be caught in the Nether without a means to get back.
A fireball will also set fire to some of the surrounding blocks (if possible), which means it’s very easy to accidentally set yourself, other players and mobs or flammable buildings on fire when a fireball explodes near you, either by dodging the fireball or by hitting it towards something.
Fighting ghasts isn’t difficult at all. Their hit points are very low, so it only takes 2 arrows or 2 blows of a stone/iron sword to kill them. A deflected fireball will kill them in one shot, as well as a fully charged aim with an enchanted bow with Power I or higher or a single strike from a diamond sword.
Deflecting fireballs is by far the best and easiest method to kill them, you don’t even need to use a weapon. As long as you pay attention not to fall down a hole or edge of a cliff, you should be fine. You can even use zombie pigmen as a shield against fireballs if you need to pause for a moment to eat food.
Using a bow and arrow does offer a nice opportunity to work on your aiming skills, which could be very useful if you plan on taking down the Ender dragon or players in PvP games. Make sure you don’t aim directly at the ghasts, but a little higher and in the direction towards which they’re flying. A ghast’s hitbox is only half it’s length, so if your arrow is fired too high, it might simply pass through it.
If you wish to simply one shot them with your sword, using a fishing rod could be the solution for you. Simply try to catch them with your fishing rod and pull them in so they land next to you. Note that it could take several tries to get it close enough, as it’ll try to float away even after being hooked and pulled.