Boss Monsters

 are normally NPCs found rarely in Terraria that are much harder to kill than other monsters. Any boss monster generally has much stronger attacks than a normal enemy, more defense, and considerably higher HP. In addition most boss monsters have their own AI, allowing them set movements to go by.

Many bosses can be summoned by an item like the Suspicious Looking Eye or Worm Food. These are the most widely known of the bosses throughout Terraria:
 * King Slime Mini-boss
 * Queen Bee
 * Eye of Cthulhu
 * Eater Of Worlds
 * Skeletron
 * Wall of Flesh
 * Wyvern Mini-boss
 * Golem
 * PaladinMini-boss
 * The Twins
 * The Destroyer
 * Skeletron Prime
 * Arch Wyvern (Xbox and Ps3 only) Mini-boss
 * Ocram (Xbox and PS3 only)
 * Plantera
 * Brain of Cthulhu
 * Ice Golem

Eye of Cthulhu
The Eye of Cthulhu (commonly referred to as The Eye) is usually the first boss players will encounter, this is due to the fact that The Eye is considered the easiest pre-hardmode boss. The Eye comes in two forms. The first form has 15 attack, while the second form has 23 attack. The Eye of Cthulhu can be summoned by using a Suspicious Looking Eye (which can either be found in random chests or can be crafted from 6 Lenses at a Demon Altar) at night. The Eye can also spawn itself if certain criteria are met. While playing, the player may get the message, "You feel an evil presence watching you...", which means that the Eye will awaken soon. After a few minutes the message "The Eye of Cthulhu has awoken!" will appear and the boss will promptly start to attack the player. You can summon The Eye anywhere, as long as it is night. Sometimes when you are under ground and you see "You feel an evil presence watching you...", and you die it will spawn after you respawn so you get killed twice in the period of 5 minutes.

Eater of Worlds
Eater of Worlds is a worm-type boss monster. He can be summoned in the corruption by smashing three shadow orbs and he can also be summoned with Worm Food, which can be crafted at a Demon Altar - however, it can only be summoned in The Corruption.

The Eater of Worlds has 53 parts in three segments; head, body and tail. To beat this boss all segments must be slain. If the head is destroyed, the next body segment will automatically take its place as a head. The same happens with the tail. If you destroy a body segment, he will split into two separate worms. Overall, if you avoid the head's massive attack of 40, the boss is fairly easy to defeat, especially with weapons that deal damage multiple times per strike, such as Vilethorn.

It is the only boss that can drop Shadow Scales, which are needed to forge Shadow Armor.

Skeletron
Skeletron is a boss which can only be defeated once per world and has no summoning item. He can only be summoned by talking to the Old Man in front of the dungeon at night and choosing the option "Curse". It is advised to be prepared because after that he will transform into Skeletron and attack you. His hands each have and his head has. His hands do 30 damage if they touch you and his head will do a spin attack that does 35 damage. Be quick to defeat this boss and summon him at the very beginning of night because once dawn comes Skeletron will hit you for 9999 damage, resulting in instant death. If you die before defeating Skeletron, you will not be able to fight him again until the next night, when the Old Man will respawn.

After defeating Skeletron, the player will gain access to the Dungeon.

Brain of Cthulhu
Brain of Cthulhu is a new boss introduced in Terraria v1.2. Brain of Cthulhu can be summoned using an item called "Bloody Spine". Otherwise, you can also summon the boss by breaking orbs similar to Eater of Worlds. The Brain of Cthulhu cannot be harmed until the Brain of Cthulhu's servants, Creepers, are defeated. On word, Brain of Cthulhu has, and teleports around the player trying to flank him/her during the fight.

Queen BeeQueen_bee.jpg
The Queen Bee is a boss that is summoned by breaking a larva type object found in a hive which spawns in the Underground jungle. Once spawned the Queen will begin to alternate between diving attacks from either side of the screen, and hovering above you, either shooting stingers or spawning tiny bees.

The Twins
The Twins are the hardmode counterpart to the Eye of Cthulhu, except there's two of them; and are both connected together as seen in the photo.

The Twins, namely Retinazer and Spazmatism, are bosses summoned with the item "Mechanical Eye", which is crafted at a Mythril Anvil after summoning and killing the Wall of Flesh. In order to make a Mythril Anvil, one must kill the Wall of Flesh, use the Pwnhammer and break Demon Alters and "Bless your world" with Cobalt, Mythril, and Adamantite.

They have similar attack patterns to The Eye of Cthulhu, but their second forms use laser and demon fire attacks respectively. The two both need to be defeated to count as a boss kill.

The Destroyer
The Destroyer is a worm type boss monster. He is the Hardmode counterpart of the Eater of Worlds. However, unlike the Eater of Worlds, it does not split into parts.

The Destroyer is summoned with the item "Mechanical Worm", which is crafted at a Mythril Anvil after summoning and defeating the Wall of Flesh.

The Destroyer drops 15-30 Souls of Might and 5-15 Greater Healing Potions. Souls of Might are required to make many Hardmode weapons and tools, like the Excalibur and Megashark. Getting the souls can sometimes be a problem, as if the Destroyer is defeated while mostly underground the Souls of Might may be dropped on top of blocks.

Skeletron Prime
Skeletron Prime is the Hardmode counterpart of Skeletron. Similar to The Destroyer, he is also made of metal.

Skeletron Prime is summoned with the item "Mechanical Skull", which is crafted at a Mythril Anvil after summoning and defeating the Wall of Flesh.

Skeletron Prime drops 20-30 Souls of Fright and 5-15 Greater Healing Potions. Souls of Fright required to make many Hardmode weapons and tools.

Plantera
Plantera is a hardmode boss with no pre-hardmode counterpart. To summon Plantera, player must fulfill a criteria; Before, the player has to defeat at least one metallic hardmode boss. After the player has met the criteria, you need to locate a pink plant which is relatively common in the Jungle. Plantera has two forms: the first form looks similar to the pink plant, with high defense. Its second form, is the pink canopy is tore off, and Plantera formely looks like a Man-eater; in this form, Plantera will speed up, lose defense, but raise its attack sharply. Plantera will always drop Temple Key and have a chance to drop: Grenade Launcher, Venus Magnum, Pygmy Staff, Nettle Burst, Wasp Gun, Flower Pow, Leaf Blower and Seedling.

Golem
Golem is technically not a hardmode boss, but he has the power and requirements of one. It is summoned by taking Lihzahrd Power Cells to the altar found in the Jungle Temple, opened with a key from beating Plantera. On the first stage he will launch various attacks at you such as extending his fists, launching fireballs and lasers. In the second stage his head detaches and you have to hit the body. Golem drops one of the following: Sun Stone, Stynger, Possessed Hatchet, Eye of The Golem, Picksaw, Heat Ray, Staff Of Earth, or Golem Fist.

King Slime
The King Slime, as one might gather, is a slime. It is blue in color and enormous, roughly 10 blocks wide and 5 blocks high. It will decrease in size and spawn blue slimes when it takes damage. It appears to have a Ninja trapped inside it.

King Slime is summoned with the item Slime Crown, crafted with a Gold Crown and 99 gel at a Demon Altar. There has been a bug associated with the King Slime, sometimes causing the boss to not spawn/appear. This may be due to the fact that he spawned inside a cave and cannot get out.

The King Slime actually drops a little amount of Gel when he dies, and all of the blue slimes spawned when the King Slime is attacked also drop gel. The King Slime also drops gold coins, a piece of the Ninja Set and some lesser healing potions.

The King Slime is the biggest slime in the game so far.

Wyvern


The Wyvern is a large Hardmode Mini-Boss. It is a large, curling, dragon-like creature that attacks at high speed.

Wyvern is not summoned - it occasionally spawns in the sky, around the same point that Harpies spawn. It spawns without warning, so the player should be careful when they are at a high elevation in Hardmode.

The Wyvern Drops 5-13 Souls of Flight and 1 gold coin.

Paladin
     Main article: Paladin

Paladin is an enemy that spawns in Hardmode Dungeons. It is big and slow walking Hallowed armor.

The Paladin spawn uncommonly in Dungeons. It throws hammers that will not go through walls at player and will try to walk in to player. When taking constant damage it will stop throwing hammers, but will still walk towards player, unaffected by knockback.