Lepus, in the mobile version.
He lays eggs, and if they are not destroyed within a small period of time another, just as strong Lepus comes out of the egg. This Lepus lays eggs in turn. Lepus can only be killed if all Lepuses are dead. According to the wiki, this guy has 20 000 HP. This guy can be fought BEFORE THE EYE OF CTHULHU. At the same time the Lepuses lay PILES of smaller eggs that hatch his filthy minions. As soon as you kill a Lepus, another one hatches very soon. The boss can be summoned even in early game if you're unlucky and find his summon.
Oh, and did I mention that this filthy, terribly designed, purely disgusting ******* of a boss
doesn't despawn when you die?
Killing this boss must take a lot of effort, right? So, you ask, what awesome rewards do you get from defeating Lepus?
I'll tell you. His drops are utter CRAP. By the time you can defeat him, they're COMPLETELY USELESS.
First off, he drops the bunny hood. Which is already obtainable by killing corrupt bunnies.
Second, he drops a weapon called the Egg Cannon. It does 16 damage. 16 damage. THE MUSKET, A GUN THAT CAN BE OBTAINED EARLY GAME, DOES MORE DAMAGE. Also, according to the wiki, the projectiles have a small chance to spawn a corrupt bunny on impact. Why would you want a gun that spawns enemies? WHY??
Third, he drops the Boots of Ostara, which make it possible to perform bunny hops. In a series of jumps, each jump will get progressively higher until a maximum of 16 blocks. Sounds good, right? The thing is, it's not an accessory. It's a pair of leggings. This make it almost useless unless you have silver armor which they combo with. And it's really hard to beat this boss with silver armor from my experience. Also, there's this thing called the shiny red balloon, which makes ALL jumps be 10 1/2 blocks, no need for a long series of jumps. The shiny red balloon can be gathered just as you get the Gravitation Potion which can be found in GOLDEN CHESTS. With a little luck you can get it WITHOUT ANY ARMOR OR WEAPONS AT ALL. And it's almost as good, doesn't take up an armor slot, and can be combined with several other GOOD accessories.
I don't even want to be in the same WORLD as this FILTHY ROTTEN PURELY AWFUL TERRIBLE PIECE OF CURSED GOLDEN SHOWER OF A VILE TWISTED UGLY DISAPPOINTMENT OF A BOSS. If it can even be considered a boss.
Also, he's so UGLY! SO. UGLY!!
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So happy to get that off my chest.