Duke Fishron

Duke Fishron is a Hardmode Boss. He is immune to the On Fire!, Poisoned, 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. The Truffle Worm is a rare Critter that must be caught with the Bug Net in underground Mushroom Biomes.

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.

First stage
Duke Fishron lunges at the player exactly five times, traveling through all blocks, 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, however they can be hard to hit.


 * Sharkron: Duke Fishron waves his fins, summoning liquid blobs that fall (bypassing any platforms) until they travel 1.5x the vertical size of the screen or impact with blocks. They then spawn Sharknadoes: giant water tornadoes that each fire several Sharkrons. The Sharkrons have limited flight range, are destroyed on impact with blocks, and can be killed by the player.

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 loops, which leave a trail of the bubbles behind.
 * 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 Sharkrons 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, as it is easy to outrun him inadvertently via that combination, wasting a Truffle Worm and requiring you to start the fight over.
 * If you use the Inferno Potion, some exploding bubbles won't hit you (if you move fast, 1 or 2 bubbles may hit you. The others won't).
 * A Cthulhunado tends to spawn at the site of Duke Fishron's death.
 * A Flairon can be useful for farming.

Trivia

 * Duke Fishron was part of an April Fools joke by Terraria staff that claimed an "Aquarian Horde" event was to be included in the game. The Duke Fishron element alone ended up actually being introduced.
 * His Sharknado attack is a nod to the 2013 movie Sharknado.
 * Duke Fishron turns transparent when over blocks, much the same way that Pigrons do.

History
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