Wall of Steel

The Wall of Steel is a boss that can be spawned in the Underworld by letting a Mechanical Guide Doll fall into lava after Hardmode has been unlocked. It is a stronger version of the Wall of Flesh.

Battle
Like the Wall of Flesh, the Wall of Steel has a mouth and two eyes. The eyes must be shot at first. Once they die, Probes and The Hungry will stop spawning out of the mouth. Before the eyes' death, the rest of the body is indestructible. When the eyes die, the mouth will start breathing fire at the player. The rest of the body will be covered with spines that inflict damage to any player that attacks it with a melee attack. The eyes each have 4000 health and the mouth has 6000. Once the mouth dies, the entire body will begin moving faster and also be open to attack. It has 10000 health. Once the body is destroyed, the drops from the Wall of Steel will be spawned inside a square of Demonite Bricks.

Drops
Only one of the following will drop
 * Coins
 * Super Healing Potions
 * Crimson Emblem (Only if the world has Crimson)
 * Corruption Emblem (Only if the world has Corruption)
 * Hellhammer (12.5%)
 * Sun Waraxe (12.5%)
 * Shadow Blade (12.5%)
 * Steel Gun (12.5%)