Boss fights are a huge part of the gameplay in Terraria as they make for a difficult encounter and also keep you progressing through tiers of equipment. This list is to narrow down the hardest boss encounters you will face throughout the game. All these bosses are hardmode bosses and including a pre-hardmode boss was too lackluster for this list. Nevertheless, all these bosses present their own unique challenges and difficulties as you face them. In an effort to simplify this list, there are no event bosses found on this list. Event bosses are more part of their own event than actual boss fights and offer a different kind of chaos to tackle.
#1. Moon Lord
The final boss of Terraria ought to be on this list. The Moon Lord simply has the highest health values, damage dealt, and unique debuffs to make him one of the hardest bosses in Terraria. This boss has 145,000; 217,500; and 277,311 total hp depending on which difficulty you are playing on and its attacks are relentless. Even with a high armor rating you would be fortunate to survive more than two attacks from the Moon Lord leaving very little room for error. There are many ways to cheese this fight and prevent yourself from taking the absurd damage numbers from the Moon Lord, but this is the case for every boss and knocking a boss’s difficulty down due to exploitable mechanics does not make sense for a list concerned with difficulty.
Not only does it have a large health pool and an almost unfair array of attacks, you have to break three different parts of this boss before exposing its heart. Of course, each part you break makes the fight harder as it adds another enemy that flies across the screen and shoots projectiles at you. Defeating the Moon Lord offers some of the best weapons in the game, so the fight becomes easier once you manage to beat him, but even with endgame gear it is still a formidable boss. To summon the Moon Lord, you have to defeat the Lunatic Cultist and destroy the four celestial pillars in order to summon him the first time. You can continue to summon him this way, or utilize Celestial Sigils made from 20 of each celestial pillar’s fragments.
#2. Empress of Light
This boss fight is a nightmare even when you do not factor in the challenge of facing her in daytime. The Empress of Light is a fight that seems nearly impossible at first glance. Learning the patterns of her attacks can help you evade her non stop attacks, but dealing enough damage to her can be a challenge. Her health pool ranges from 70,000; 98,000; and 124,950 depending on which difficulty you are playing on. Her attacks are akin to a bullet-hell game where the entire screen is filled with projectiles and various beams of light. This boss fight is one of the most visually impressive fights of Terraria and was one of the last bosses added during Terraria’s Journey’s End update.
One of the best summon weapons in the game is locked behind fighting the Empress of Light and defeating her with damage done only during daylight. The problem being, she will kill you in one hit if you fight her in daytime. Empress of Light enraged gives Moon Lord a run for its money and beating this challenge would require a minimum of hours of practice against her attacks. You can summon the Empress of Light by killing a prismatic lacewing which spawns in the surface of hallow biomes after you have defeated Plantera. You can capture this butterfly with a bug net to summon the empress at a later time. If you have trouble locating this critter try keeping a lifeform analyzer on hand to detect whether or not one of these butterflies has spawned nearby.
#3. Duke Fishron
One of the most mobile bosses in Terraria and a nightmare to face when unprepared is Duke Fishron. This shark/pig/dragon abomination is quick to move and has high HP to boot. His health ranges from 50,000; 60,000; and 76,500 depending on which difficulty your world is set to. He flies in erratic patterns and attacks with sharknados, explosive bubbles, and a ghostly charge attack. Duke Fishron offers some of the best equipment pre-Moon Lord and is recommended to tackle after Golem or Plantera. You can face him much earlier in hardmode to skip to better equipment if you are confident enough. He becomes enraged and deals double damage if you leave the ocean biome. This makes his fight awkward as most of the ocean biome will not scroll and it can be disorienting moving your player and the screen does not pan side to side. Moving too high or too far from an ocean makes the fight nearly impossible as his attacks will deal double damage.
You can summon Duke Fishron by first catching a truffle worm from glowing mushroom biomes underground. Truffle worms are wily and will attempt to escape the player once you get close so close the distance quickly while swinging a bug net to capture this elusive worm. Fishing in an ocean with one of these worms in your inventory will spawn the boss after you reel in a catch. Once you get him low enough his skin will turn darker and his eyes will glow yellow. He will disappear and reappear to quickly charge at the player. Attempt this boss fight only if you are confident in quick repositions and can deal decent damage.
Plantera is one of the biggest hiccups I face when going into a new world. Fighting bosses is all about preparation and set up beforehand. However, the jungle becomes very hostile in hardmode and a wayward spinning tortoise dealing over 200 damage can throw a wrench into the works when fighting a boss in a twisting jungle. Plantera is one of those bosses that is easy to underestimate and even with careful planning can slow you down. This large plant monstrosity spits thorns, attempts to close in on the player with barbed hooks, and can charge at the player surprisingly quickly. Its health values range from 30,000; 42,000; and 53,549 total health.
One of the difficulties with Plantera is simply the fact that you have to fight it in the jungle. If you attempt to leave the underground jungle, plantera will become enraged and attack at a higher rate, move faster, and chase you until you die or plantera dies. Plantera can also poison you befitting the toxic environment of the jungle, and its rapid fire shots can cause grief if you are trying to keep a line of sight to this boss. You can summon plantera by breaking a plantera bulb that spawns in the jungle after defeating all three mechanical bosses. This is another part of why Plantera is so frustrating as you have to wait for these bulbs to grow before attempting to fight it again.
#5. The Twins
Finally we arrive at The Twins which is odd considering its counterpart is one of the first bosses you face in the game. The Twins are a mechanical boss variant of the Eye of Cthulhu and surprisingly offer a bit of challenge. They exist as two entities called the retinazer and spasmatizm. The former having a range of health of 20,000; 30,000; and 38,250. The latter having a range of 23,000; 34,500; and 43,987. Despite spasmatizm having a higher health, it is recommended to focus this one down first as it cuts off a lot of space during the fight. Both of these bosses transform at half HP similar to the Eye of Cthulhu and will attack more aggressively and at shorter intervals. If you are playing on expert or master level difficulty these attacks become even more difficult to avoid.
The Twins can be summoned at night with a mechanical eye which can be crafted with 5 iron/lead bars, 3 lenses, and 6 souls of light at a mythril/orichalcum anvil. The Twins are difficult at early hardmode stages of the game especially because of preconceived notions that the mechanical counterpart of the Eye of Cthulhu would be easier than the others. However, having two flying eyeballs targeting you with lasers and fireballs makes for a relatively difficult fight and one that subverts expectations.
Q. How do you beat the Empress of Light during daytime?
There is no quick and easy fix to beat the Empress of Light, you can exploit teleporters and an exploit called hoiks to defeat the Empress without much worry. To beat her without exploiting game mechanics all you can do is practice against her attacks during the night. Her attacks follow a pattern that can help you understand which attack is coming next and how to avoid them. Be patient and keep trying to beat it, a challenge is more rewarding if you do not cut corners.
Q. How do you beat the Moon Lord in Terraria?
Like with other boss fights, you have to understand its attack patterns and where and when to dodge in order to beat the Moon Lord effectively. Getting hit once is disorienting as almost every attack afterwards can be lethal, but its attacks are telegraphed with a wide margin and the patterns can be easier to follow after a few attempts. Having a decent pair of wings to accelerate upwards quickly and avoid the rotating laser beams can help you conquer this boss fight.
Q. How do you summon the Dreadnautilus?
The Dreadnautilus is an event enemy that can be spawned by fishing during a blood moon in hardmode. It is not technically a boss, but it does follow similar rules to other bosses such as requiring being defeated before dawn. You can also fish other enemies out of the water during a blood moon and the Dreadnautilus happens to be the rarest one you can catch. It offers a decent summon weapon as a 50/50 drop.