Duke Fishron

Duke Fishron is a Hardmode Boss, and is currently the most difficult boss in Terraria. He is immune to the On Fire!, Poisoned, Cursed Inferno, Venom, and Frostburn debuffs.

Summoning
Duke Fishron is summoned by casting a Fishing Pole into one of the two Oceans while having a Truffle Worm in the player's inventory to use as Bait.

Summoning Duke Fishron does not require that any other bosses have been defeated beforehand, but a world must be in Hardmode in order to obtain the Truffle Worm used to summon him.

Attacks
Duke Fishron flies quickly in all directions and travels through blocks.

First stage
Duke Fishron lunges at the player exactly five times before using one of two projectile attacks:


 * Detonating Bubble: Duke Fishron blows roughly 20 bubbles from his mouth that follow the player at moderate speed, exploding and dealing damage on contact. These bubbles can be destroyed via any attack or projectile.


 * Sharkron: Duke Fishron waves his fins, summoning liquid blobs that fall (bypassing any platforms) until they go 1.5x the vertical size of the screen or they hit the ground, and create tornados ("Sharknados") that spawn several Sharkrons (fish projectiles), which charge at the player. The Sharkrons have limited flight range.

After a projectile attack, he lunges another 5 times, beginning the cycle again.

Second stage
When Duke Fishron falls below 25,000 health, he remains stationary for a second and his eyes glow. His damage, speed, and defense increase significantly. His lunges become faster, and are only performed three times instead of five before executing one of his projectile attacks, which are also upgraded:


 * Detonating Bubbles are now fired while Duke Fishron flies in quick circles, which leaves a trail of the bubbles.
 * There is now only one "blob" that causes the tornado, but it follows the player, creating a "Cthulhunado" (upgraded version of first stage's "Sharknado") on contact. The blob itself does not cause damage, but will spawn twice as many fish as in the first stage.

Tips

 * If you get far enough away from Duke Fishron, he will despawn, like most bosses. Take care when using the Frog Leg with Fishron Wings and other movement boosts, as it is easy to outrun him inadvertently, wasting a Truffle Worm and needing to start the fight over.

Trivia

 * He appears to be a fish-pig-walrus-dragon hybrid, as opposed to the Pigron, a mere pig-dragon.
 * One of the many Fish that can be caught is named Fishron, though it resembles a Pigron instead of Duke Fishron.
 * This is the only boss that must be summoned at the Ocean.
 * Duke Fishron was originally an April Fools joke that was partially implemented. The original joke included another new boss and two new Events: the Conch of Fish, the Aquarian Horde and the Tidal Moon, with the ocean biome being completely destroyed in the process of these.
 * Duke Fishron is summoned by a Truffle Worm, which may be a reference to the Truffle saying that a pig ate his brother.
 * The tornadoes summoned by Duke Fishron are called Cthulhunados, probably to add to the game's ongoing Cthulhu trend.
 * One of the sounds made by Duke Fishron, namely the sounds he makes when summoning Sharknados, is also used by Pigrons when they are approaching the player.
 * His Sharknado attack may be a reference to the 2013 movie Sharknado
 * He might also be a reference to the Deep Ones or the Great Ancient Ones from Cthulhu Mythos

History
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