Wall of Flesh

The Wall of Flesh (commonly refered to as WoF) is an aptly named wall made out of flesh that has the height of the entire map but its vital points (eyes and mouth) are in the open Underworld.350px

The Wall of Flesh has two eyes that shoot lasers, and the mouth in the middle spits out leeches which chase the player, usually after the total health of the Wall of Flesh has been reduced.

The eyes and "mouth" are actually reskins of Eyes of Cthulhu. The one being the "mouth" is the reskin of the Eye of Cthulhu in its second phase, and the other 2 eyes are reskins of Eyes of Cthulhu in their first phase.

The Wall of Flesh is also accompanied by small flying enemies called The Hungry, which will detach and throw themselves at the player when damaged enough. The Wall of Flesh only takes Damage at its eyes and the mouth, which means that you have to aim for those when trying to defeat it.

The Wall of Flesh will disappear if he makes it to the edge of the map, however, it will always travel towards the center of the map upon being spawned, giving players the maximum space to defeat it.If you die while fighting the Wall of Flesh, and make it to the Underworld in time, you can continue fighting it. If you come up from behind though, you will be grabbed by one of the Hungry, and launched through the wall.

When the Wall of Flesh dies it leaves behind a square of demonite blocks containing all of its drops.

The boss will only spawn in the Underworld, you have to kill the Guide by throwing the Guide Voodoo Doll in the underworld lava (you have to throw the Doll in the lava, just equipping the Doll and killing him  will not work  Also there must be a living gude present or the Wall will not spawn.). When you see it, it leaves you with the Horrified debuff, that renders you unable to leave (It will kill you if you try).

If you die fighting the Wall of Flesh, the debuff will stay on you for whenever you're battling the Wall, but it allows you to leave, ''but you cannot respawn the beast unless there is a living Guide in the world with housing. Only then will throwing the voodoo doll summon the boss. If you throw a Guide Voodoo Doll in the lava while The Wall of Flesh is summoned it won't do anything.''

Also, there is a bug where the Horrified debuff might stay on the player even after being killed by the boss, preventing the player from battling it again.

The Wall of Flesh is also summoned by just being in the underworld - meaning that you don't always have to throw the Guide Doll into lava for it to spawn. Though the current mechanic for summoning the Wall of Flesh via this method is not known, just "being in the Underworld" makes it appear. It should be noted that the Wall of Flesh may be summoned with the Guide Doll, if a Voodoo Demon drops it into lava upon death.

If you get trapped in a hole while the Wall of Flesh is coming towards you and you don't get out in time, you will get launched through the blocks by the Wall of Flesh so the fight continues, however, this doesn't work if you are at the edge of the world, as it will crush you.

If you attempt to leave the Underworld during the fight by using a Magic Mirror, your character will die, due to the Horrified Debuff. Your lost coins, however, will be found at your spawn point.

Strategy
Recommended pre-hardmode equipment:

Armor

 * A full set of Jungle Armor, for Magic attacks.
 * A full set of Necro Armor, for Guns, Bows, etc.
 * A full set of Molten Armor, for melee attacks.

Weapons
A ranged weapon or magic spell, such as:
 * Phoenix Blaster with Meteor Shot or Silver Bullets
 * Molten Fury with Hellfire Arrows
 * Demon Scythe with a sufficient number of Mana Potions
 * Star Cannon with around 200 stars and good accuracy

A decent melee weapon to deal with swarms of enemies such as:
 * Night's Edge
 * Muramasa
 * Fiery Greatsword

Accessories

 * Cloud in a Bottle or Cloud in a Balloon
 * Spectre Boots
 * Obsidian Shield
 * Mana Flower (allows for automatic Mana Potion consumption)

Additional defensive items, such as a Warding Shackle or a Band of Regeneration with a defense bonus are optional but recommended.

Misc Equipment

 * Grappling Hook or Ivy Whip
 * Grenades (optional but potentially useful against The Hungry)
 * Dynamite (Make a bridge out of Dungeon brick or Hellstone ore becuase they are immune to explosions. About 20 - 30 kills the wall, and this method kills him the fastest.)

Potions

 * Healing Potion (at least 5 for healing)
 * Ironskin Potion (for extra defense)
 * Obsidian Skin Potion or Water Walking Potion (for dealing with lava)
 * Mana Potions (for magic-users)

Any other buff potion is potentially useful.

Combat
As the boss is fought in the Underworld, it is best to prepare beforehand by building bridges over any lava or a long wooden platform in the upper part of the Underworld, in order not to be slowed down by obstacles such as buildings and still be able to attack the lower part of the boss with ranged weapons; alternatively, you can use a Gravitation Potion to "fly" over terrain. Using an Obsidian Skin Potion/Water Walking Potion is also incredibly useful to minimize external damage from the Underworld's hazards. It is also a good preemptive measure to place Torches on the platform, as fighting in the dark can make it hard to see the Hungry and Leeches chasing you, however, due to the lava in the Underworld, sometimes a light-producing weapon or an Orb of Light would suffice (if you have defeated him before, the Fairy Bell would also work).

When the boss is spawned, there is a high chance that it will come from behind you, therefore it is recommended that you make sure the direction you're facing is the way you can run. The Wall will travel in a single direction and you cannot go in the opposite direction as the boss will be in the way. Therefore, it helps to go to either end of Underworld and summon it from there.

It is also recommended to aim at the wall's eyes, since they have a lower defense than the mouth. However, at certain times it can be covered by ash block, so make sure to aim at the mouth during this time to maximize damage output.

The Wall of Flesh is the hardest boss in the game before it is defeated (it is tougher than Skeletron). Therefore, it is advised to get the best Hellstone armor and weapons before fighting the boss.

The main challenge in fighting the Wall of Flesh is to deal with the Leeches and Hungry that it spawns. It is recommended to kill them using weapons that can deal a vast amount of damage to multiple targets, such as Grenades, the Phoenix Blaster with Silver Bullets or Meteor Shot, a Molten Fury with Hellfire Arrows, or the Demon Scythe. Having a friend help with pinpoint weapons to fend off isolated monsters will also help.

Also be aware that both the Eyes will shoot lasers at the player; beware of these. A Cloud in a Bottle/Cloud in a Balloon and/or Rocket Boots/Spectre Boots are a must to fight this boss, or you'll be slowed down from every hill in your path and likely get eaten (again, you can use a Gravitation Potion to move over the terrain). Melee weapons do not work terribly well against the wall, due to the fact that the wall can easily damage you at any range.

Since the greatest danger of the fight are Leeches and The Hungry knocking the player into the boss or lava, the Cobalt Shield or Obsidian Shield is a must-have. Although the Molten Armor provides the best defense, in order to deal more damage (which is vital as the boss will eventually push you into unfavorable terrain) one can equip Jungle Armor (which works greatly with Demon Scythe and mana economizing accessories) or Necro Armor (to boost the damage output from guns and bows). Meteor Armor is not recommended for a caster, as it provides significantly less defense.

It is impossible to sneak up on the Wall of Flesh after he has been summoned, as one of his tendrils will grab you from several hundred feet away and fling you in front of him before you can even get in range to attack.

Rewards
When the Wall of Flesh is defeated, it will spawn a large box made out of Demonite Bricks, with its loot inside, destroying anything in the way so nothing gets lost. It will drop money and hearts, and will always drop the Pwnhammer.

It will also drop one of the following items:


 * Laser Rifle (Powerful, Rapid-fire Mana-based laser)
 * Breaker Blade (Gigantic sword, Larger reach than Blade of Grass and about the same damage as Night's Edge)
 * Clockwork Assault Rifle (Fires in 3 shot bursts, while only consuming one ammo)
 * Ranger Emblem (Accessory that adds 15% ranged damage)
 * Warrior Emblem (Accessory that adds 15% melee damage)
 * Sorcerer Emblem (Accessory that adds 15% magic damage)

Also after defeating the Wall of Flesh, Corruption will start spreading through sand, stone, sunflowers and the jungle. This can be countered by the new Hallow biome. This allows access to the new items introduced in 1.1. The time after killing the Wall of Flesh is known as 'hard mode' (only after you've mined a Demon Altar). This is because new mobs spawn that can kill the player easily.

Bug Fixes

 * One way to fix this bug is to enter/create (then enter) a different world, let any monster besides the WoF itself kill you, exit the game, and come back to your main server where you had the Horrified debuff glitch. The debuff will be gone after dying by a monster in another world.
 * Fighting another boss such as Eye of Cthulhu, Eater of Worlds (on the same world) should allow him to be spawned again
 * If the Horrified debuff remains and the Wall of Flesh cannot be summoned, close Terraria and restart it. The debuff should not appear upon returning to The Underworld.