Editing Terraria (section)

===Hardmode===
* Queen Slime: A Hardmode version of King Slime that can fly. Summoned using a special crystal found in the underground Hallow.
* Mechanical Bosses: Remixes of previous fights, all required for reaching the final boss. Lore says they were built to replace damaged/lost parts of Cthulhu by the Cultists (them clearly not knowing he could just grow them back), with the brain replacement unfinished (unless you're running a mod that adds an interpretation of what a mechanical Brain of Cthulhu would be) when you barge in and ruin their hard work. They spawn at night after you pwn(hammer) an Altar until all three are dead.
** The Twins: The Hardmode version of the Eye of Cthulhu, only there are two of them (Retinazer and Spazmatism), and you have to fight them at the same time. Retinazer shoots lasers and Spazmatism breathes cursed flames, and Spazmatism is the only one to retain the EoC's mouth second phase (Retinazer has a new second phase which shoots stronger lasers). Summoned manually using a Mechanical Eye.
** Skeletron Prime: The Hardmode version of Skeletron. Has four arms instead of two, and instead of hands has various weapons. Also gains spikes when going for a skull ram. Summoned manually using a Mechanical Skull.
** The Destroyer: The Hardmode version of the Eater of Worlds that shoots lasers out of the segments of its body, and spawns laser drones if said segments get hit enough. [[FAIL|Gets utterly raped by the Daedalus Stormbow]]. Summoned manually using a Mechanical Worm.
** Mechadusa: A fucking abomination made of the 3 mechanical bosses fought on a special worldseed. Save the Skeletron Prime portion for last because it chains down the other two. Summoned manually using Occram's Razor, named for the logic concept (and possibly for Ocram, the old Hardmode boss that also dropped souls). Can be considered an alternative to fighting all 3 separate bosses at once for the achievement.
* Plantera: A giant plant monster. The Bulbs needed to spawn it will only spawn when you defeat the Mechanical bosses; one is now guaranteed to immediately grow once all 3 have been killed in modern versions at least, but otherwise, God help you if the World Evil is slowly eating the Jungle (though this is less of a problem on modern versions as well since instead of it permanently becoming a mound of evil dirt it can be turned back into pure Jungle). Required for reaching the final boss.
* Ocram: The final boss in the original Console release, and now only accessible if you have an Xbox 360/PS3/PS Vita/Wii U/3DS, it requires a Suspicious Looking Skull and is extremely expensive to produce due to the materials required to make it. Drops Souls of Blight which are used to craft the console edition's endgame sets and weapons. Its name is actually just its programmer's backward (Marco), and coincidentally resembles the Moon Lord that would take its place (making some wonder if Ocram at least partially inspired its final design). Referenced posthumously in a death message in modern Terraria, as well as a stretched reference in the Occram's Razor summon item for Mechadusa.
* Golem: The boss of the Jungle Temple, only accessible in Hardmode. Can only be accessed by killing Plantera, going to the Temple, and activating the Altar in its heart. Required for the Lunatic Cultist to be accessible. At the stage of progression it's supposed to be fought at, [[FAIL|it's somewhat underwhelming]].
* Duke Fishron: Half fish, half pig, and half dragon. Found by fishing using a special truffle worm, and is completely optional for progression. Gains an extra phase with invisibility (sans eyes, which are the only always-visible part of this phase) and reduced visibility in Expert Mode, which is pretty annoying to fight.
* Empress of Light: Big butterfly fairy. Summoned by killing a special butterfly that only spawns in the Hallow. Becomes a one-hitting superboss during the day, which, if you manage to beat it (entirely during the day - no cheating by having any part of the fight happen at night, you pussy), drops the best summon weapon in the game.
* Lunatic Cultist: A devotee of the Moon Lord. Killing him summons the four Celestial Pillars/Towers, which are bosses, invasions, and temporary semi-biomes in one. Spawned by killing his underlings worshipping a Moon Lord-depicting tablet outside the Dungeon.
**The only modern boss to not have a grab-bag in Expert/Master Mode, probably since he's also the only one to not have any difficulty-exclusive items.
* Moon Lord: [[BBEG|The final boss]]. Confirmed to be a very weakened Cthulhu in a lore forum post, having gotten his shit kicked in (and an eye and brain ripped out, though it appears he just regrew them) and banished to the Moon by the Dryads (it cost them all but one member of their race, [[Grimdark|though that's to be expected when fighting a Great Old One]]). It's your job to finish him off. He spawns after killing all Celestial Pillars/Towers or using a Celestial Sigil, though the latter only becomes accessible if you've done the former at least once. Drops several of the best weapons in the game, including the last few components for ''the'' best, the Zenith.
**Originally planned to be a completely different boss that was essentially [[Atropus|the moon falling on the world a la Majora's Mask]]. Got changed to be Cthulhu at some point, either to bring the game full circle from killing Cthulhu's eye or because the falling moon idea would be too hard to make.

The Bosses may drop trophies as well. In Expert Mode, they drop some exclusive gear, and in Master Mode, you get pets and even bigger and grander trophies.

The only bosses that need to be killed to beat the game from a fresh character and world are technically Skeletron, Wall of Flesh, all the Mechanical Bosses, Plantera, Golem, Lunatic Cultist, and Moon Lord, but missing the gear and resources of the other bosses ''will'' make things much harder. Especially the World Evil bosses since Hellstone (and therefore a lot of Hardmode shit) are locked behind an evil pickaxe (unless you're in an old version where the Reaver Shark is still a substitute for an evil pickaxe, in which case this is easily rectified by just fishing in the Ocean - or God forbid a version where [[What|the Drax is obtainable in Shadow Chests]] which basically makes mining up to mid-Hardmode trivial).