Dreadnautilus

The Dreadnautilus is a Hardmode miniboss that is summoned by Fishing at an Ocean during a Blood Moon.

Attacks

 * It will spin around the player for about ~3 seconds.
 * It will fire a spray of red projectiles at the player.
 * It will briefly glow red and summon three red symbols.
 * It will summon multiple Blood Squids.

Tips

 * It is recommended to have an arena set up with platforms.
 * The Dreadnautilus cannot be summoned if another biome takes priority over the Ocean, such as a Graveyard.
 * Using summoning weapons could be useful, as they could deal with the Blood Squids while the player can focus on the Dreadnautilus.
 * It is recommended to have a Leather Whip and tag the nautilus with it so your minions will target him and you can fight the squids (or vice versa).
 * If you have a Bloody Tear you can summon the Blood Moon in when it is fought. (Moon Lord must be defeated to obtain this item)

Trivia

 * It resembles a.
 * Its name is a portmanteau of "dreadnought" (a class of warships) and "nautilus."
 * Its original name was "Blood Nautilus" in an official trailer.
 * Its eye appears to be bleeding.