Wall of Flesh

. The Wall of Flesh (WOF) is a boss located in The Underworld. Beating it will trigger Hardmode.

Summoning it
To summon it, a Guide Voodoo Doll must be thrown (or otherwise fall) into lava in the Underworld; the Guide must also be alive at that point in order to let the summon be successful. With the Guide sacrificed, the Wall of Flesh will spawn from the direction you are looking and instantly cast the Horrified debuff on all players, which will last until the Wall or the players die.

Attacks
The Wall of Flesh has several attacks. First, it has tiny mouths called The Hungry, attached by a long vein, which move towards and damages players. As the Wall of Flesh's main body takes damage, these mouths deal more damage, and become more resilient to attack. It is therefore advised to take care of them first. When they've suffered enough damage, they will detach and attempt to fly into players. Furthermore, the wall has eyes that will shoot lasers. As its health decreases, the lasers increase in damage, speed and frequency. Finally, it will spit Leeches out of its mouth, which chase players.

Trying to escape
If a player attempts to escape from the fight by physically going away or if they try to get behind the Wall of Flesh somehow, the mouth will release The Tongue, which will cling onto players, drag them in front of the mouth, and deal a large amount of damage while leaving the player immobilized in the process. If you approach the wall from behind (usually by having died and trying to catch up to the wall in order to finish it), the tongue will only appear if you are in reasonable proximity. Using the Magic Mirror at any moment during the fight causes instant death, with the message “ tried to escape”. As the damage caused by this effect occurs after the teleportation, the Mirror can be used as a last-ditch attempt to conserve items/money - they will drop next to the spawn.

Killing it
To destroy the Wall of Flesh you must attack its eyes or its mouth. They all share the same life counter, so shooting at any of the three will deplete the boss' total health. The "wall" itself is transparent to weapons, and shooting the Wall of Flesh there will not deplete its health. Unlike other bosses, this boss does not despawn if you die: it will remain alive until it reaches the other end of the map. Trying to summon it again before it despawns will simply destroy the Guide Doll (and kill the new Guide if one has arrived already).

Aftermath
When the Wall of Flesh is killed, it leaves its drops in a fully enclosed box of Demonite Bricks so they don't fall into lava, although if they did, only the Coins and Hearts would be destroyed.

After defeating this boss, your world will enter hardmode and you will face tougher enemies. This will also generate two diagonal stripes of The Hallow and The Corruption somewhere, usually near your original spawn point. To visualize this, they will form a V or X. These lines extend from The Underworld to the top of the map, therefore creating biomes of Underground Hallow and Underground Corruption. Floating islands can also be turned into Hallowed and Corrupted variants. The generation of these lines effectively means players must take far more extensive measures to stop the spread of biomes.

Tips

 * Certain consumables such as Water Walking Potion, Gravitation Potion and Obsidian Skin Potion can make traversing the underworld much easier.
 * The Wall of Flesh's spawn location is determined by where the Voodoo Doll was thrown in relation to the center of the world. Thus, you can get the maximum space to fight the WOF by reaching the edge of the world and throwing the doll toward that edge.
 * The use of heart statues is recommended, as they provide hearts (healing 20 HP) every time they are activated.
 * Preparing the underworld for the battle is advised. Having a reasonably long straight path with no danger of getting stuck or falling can make the battle significantly easier, and can even block lasers from the lower eye if the path is at the proper height.
 * Many bugs are present (In the worst case the Wall of Flesh will give you "The Tongue" condition, rise up until it reaches of the top of the map, and there's no escape out of this!) so world-backup is recommended.
 * Using rocket boots can be very helpful, as they will allow you to fly over most obstacles that you'll encounter while trying to avoid the Wall of Flesh.
 * Building a platform of dungeon blocks then throwing dynamite at the Wall of Flesh is an easy way to kill it.

Trivia

 * The treasure box can intersect other blocks or treasure boxes without losing its contents.
 * If you start the battle in the same place multiple times, you can leave the treasure box intact to mark your record time.
 * It is possible to have the box spawn on you if you are overlapping the Wall of Flesh when you kill it.

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