Minecraft is what a Terraria avatar sees from his/her point of view.
Spazmatism is the original Eye of Cthulhu.Retinazer's second form is an eye with a laser turret, but Spazmatism's second form is a mouth.
HERO is (the Terraria universe's) Link.He wears the Hero's Clothes a lot, he defeats huge monsters while being significantly weaker than those using ingenious techniques, and he wears the Hero's Clothes a lot.
Corruption is a manifestation of human evilA long, long time ago, a Gigyas-esque monster of some description crash-landed in a metorite on a polluted, dying alternate version of Earth, destroying what remained of its biosphere and shifting its geological activity into overdrive. The humans retreated to what would eventually become the floating islands while mass earthquakes and volcanoes reshaped the earth into a shape unrecognizable to us, even when the magma hardened. The creature that arrived with the meteor drew power from human evil, and took a form representing it- specifically, the perversion of nature, hence the purple grass- and began to take over the dead world. It created the monsters that spawn in corruption to protect itself, and began storing power in the shadow orbs to sustain itself. This explains why destroying them summons the Eater of Worlds.
Non-corrupted life in Terraria is genetically modifiedAfter the catastrophie mentioned above, scientists on the floating islands went about creating life that could replace what was destroyed in the event. They eventually came out with several fast-growing, fast-spreading strains of plant life that reclaimed almost all of the Earth's surface in the years that came before the game itself. They also inserted direct copies of life that existed before the event into this replacement biosphere, but these animals had to eat something. The genetically engineered plant matter jump started their evolution- slimes are basically macroscopic bacteria, the worms are- well, worms- undead enemies are the result of parasitic organisms- zombie parasites evolved to replace the nervous system, while skeletons eat the remaining flesh and use it to construct a sort of muscular system in the bone marrow channels. Goblins are the descendants of those few non-islander survivors who had no other source of food. Why other animals are not there, I don't know. Maybe they were out-competed by the other organisms. As for demon enemies? Maybe they're just demons. The Hallow was created during a meteor shower. One of the meteors was actually the exact opposite of the Corruption, and when it hit the earth, the Corruption entered a defense mode to make sure it would stay alive. Seeing the danger that both entities created, the gods went on the surface of the planet itself. Using a pile of flesh, the gods then sealed the Hallow, but the Corruption proved too much to seal completely, so instead they sealed away most of it. Having been greatly weakened, the Corruption could no longer spread through rocks. Then, to make sure the seal would remain strong, they linked the pile of flesh to a voodoo doll representing a human. However, during the creation of the link, the pile of flesh grew eyes and a mouth (Corruption), and became sentient (Hallow). the newly created Wall of Flesh then ran amok, killing many humans and in turn creating the jungles out of the remains of the civilization. The gods then used the last of their power to seal the Wall of Flesh into the Underworld, and before vanishing, entrusted the voodoo doll to a lone Demon, and sent their Harpies to protect the floating islands. The human species having been driven to extinction, many of their creations started to evolve drastically. A group of primitive monkeys evolved into Goblins, while another evolved into primitive humans. Goblins ignored the humans, because they did not know of their power. Meanwhile, a group of royal slimes controlled by a ninja became known as King Slimes, and placed slimes around the world into a tyrannic empire. A couple of hundred of years later, an elderly man, known for his legendary weaving skills, came upon the dungeon. Upon trying to descend deeper, the Dungeon Guardian attacked and put the Clothier under a curse, becoming linked with him. The curse soon evolved and took over the Clothier's mind, becoming Skeletron in the process. A few years later, the Eye of Cthulhu was created when a Demon Eye mutated upon making contact with the rotting corpse of a primitive Cthulhu. It then flew into the night, never to come back until it felt enough souls to eat. Meanwhile, the Eater of Worlds had come to life from a lone Devourer, becoming linked with the Shadow Orbs. Having seen this, the present Cthulhu, having traveled into the past, cloned the Eye, Skeletron, and the Eater, and took the clones with him into the present, having plans of roboticization. One thousand years later, The Twins, The Destroyer, and Skeletron Prime were successfully created a few hours before Cthulhu died from wounds when a primitive Skeletron Prime attacked him. With his last words, he told them to never attack the human race, unless said humans summoned them. However, an enormous meteorite containing a wild essence striked the rotting corpse of Cthulhu, creating a big hole and killing life around it. Then, the unexpected happened: The essence reacted to the presence of Cthulhu's blood, and created a substance that started to spread wildly, turning trees and the grass red in doing so. The essence also reacted to the brain, but this time, it had a much bigger reaction: Cthulhu's brain started mutating, and grew a heart with an eye inside of it. The brain, now pulsing with life again, started creating life that could survive in the Crimson. Upon doing so, it sealed away most of its essence inside giant hearts, and disappeared, plotting to take over the world with its legion.
The world and the people who remain are what is left of a vast Magi Tech Society that destroyed itself.They developed a certain level of technology that allowed them to better interact with the magic that existed in the world itself. Societies that were enemies and competing for the resources that fueled this technology went to war. Things spiraled out of control and they destroyed their societies reducing them to a more primitive state compared the height of their technology. The dungeons are various storage, living quarters, old labs, etc that are left over from the societies and the war. This is why they contain rare items. Part of their tech involved using magic to change life to suit their own purposes resulting in things like the slimes and giant worms. The creatures like demon eyes and zombies are the end result of a mad scientist like campaign to make the ultimate weapon. The various boss monsters are the more powerful results of the experiments. Skeletron's "curse" is really a scientific experiment that had unexpected results and he is in fact immortal. The long life, knowledge of what he became and used to be as well as his part in destroying society, have driven him to the point of desiring destruction which is why he challenges you. He is also guarding the most secure facilities to prevent the items inside from falling into the wrong hands. Believing anyone who will not free him from his curse has ill intentions is why he kills you if you penetrate the dungeon without destroying him first. The various enemies in the dungeon are a back up security system powered by various Magi Tech experiments that protect what is left inside. Enemies like demons and bone serpents are unique creations of the mad scientists and set to guard a potent resource that was likely used to fuel the war. The war had additional side effects like unintentionally making multi-dimensional travel possible between the various worlds. This also affected the remaining humans. When they die it causes a form of paradox that the last scientist created a band aide fix to. The paradox resolves it self by returning you to key points in the world where you have left a form of "imprint". The reason you can respawn at beds is because when you have vivid dreams it makes a new imprint in the world. As part of the effort to mobilize as much of their populations for war as they could, they implanted via magic and other means, the knowledge of engineering, design, manufacturing, and weapon usage. they also gave their people limited control of small pocket dimensions for storage as well as means to view it in their mind and recall the items into the world they are in currently. As the effects of the damage to fabric of space and time of the world settle they will cause new biomes, items, and monsters to appear in the world. This also alters how far one can travel in the land. The corruption resulted from an experiment with exotic manufacturing and storage with Magi Tech that went horribly wrong. The remnants of this are the dark orbs scattered about in pits where Magi Tech factories used to exist. The factories were powered by orbiting meteor that exerted gravity on an invisible beam of magic to the heart of the factories. Which is why when you smash them they come crashing to the earth as that interaction is the only thing keeping them aloft outside the atmosphere. The factory zones had Magi Tech creatures tied into the landscape around them which is why there are Soul Eaters, Devourers, and the Eater of Worlds atmosphere. The delay in destruction of the orb and the meteor falling is due to slowly decaying resistance of the beam once it's generator is gone. The factories and the creatures which are powered by the same tech linked to the dark orbs emit a pollutant that causes the corruption. In their last ditch efforts to atone for their mistakes the remaining scientists modified the sunflowers to be powered by magic derived from sunlight to halt the spread of the corruption by cleaning it up in the areas next to the sun flower. They also developed the purification powder to allow the survivors to make the land habitable again.
The Shadow Orbs are Soul Jars.This explains the screams you hear when you break them, and why the Eater of Worlds gets PISSED and starts attacking you when you break the soul-pantries of the Eater of Souls. Alternatively, the Soul Eaters could just be harvesting the souls and, rather than eating them for sustanance, be transferring them into the Orbs to use as some sort of energy for the Corruption.
Source of magic/corruption is the stars/space,Think about it. You can only gain mana from combining Fallen Stars into Mana Crystal. And destroying shadow orbs summons meteors. And Meteor armor regenerates mana and Space Gun uses mana.
The corruption is trying to eradicate all magic.The shadow pearls contain magical essences, the magical essences escaping causes meteors to fall, so when too much magic has been freed, the Eater of Worlds gets mad and tries to stop you from gaining access to more magical equipment. Purification powder is also obviously magical.
The Meteors are solid magic constructs mined by the previous civilization.The factories of the Magitech civilization, more than being fueled by the Shadow Orbs keeping the meteors aloft, were fueled by the magic of the orbiting meteors. When you craft armor and tools out of this solid magic by refining it, the inherent properties enhance and feed off of your own magical energies. The Corruption is the result of unshielded magic being siphoned down into the earth by the shadow orbs. Eventually using Meteorite tools and armor will result in you too being corrupted by its power.
Terraria is actually a 3-D universe.However, two transparent walls have squished all terrain, blocks, and people into a flat plane of existence. The enemy mobs hate this, and attack everything they see because maybe it will undo the Curse of Two-Dimensionality. The NPCs enjoy their new, simpler lives and remain friendly. And the Player Character is the one who cast the spell, all for your personal enjoyment.
The Corruption is an extremely short and wide herbivore.It's slowly nomming the grass, which turns it purple, and it spreads through the cracks in stone very easily due to its odd shape. The little purple dots it gives off are spores for it to grow elsewhere. It also hosts symbiotic bacteria, which eventually group into Vile Mushrooms. If left unattended, the Vile Mushrooms hatch into Little Eaters, who slowly grow as they consume the corruption spores. Eventually, they'll group into Devourers, which prey on the smaller Eaters of Souls. In rare cases, the gases from a broken Corrupt Orb will instantly transform a well-fed Devourer into the Eater of Worlds, and it will go berserk from the sudden change. Otherwise, the Eaters of Worlds grow naturally from the Devourers, and spend time underground until they detect Worm Food and the presence of Corruption, when they attack. There, I explained Corruption without mentioning magic OR evil.
The Guide is a somewhat benevolent Elder God in human form.He is helping the protagonist in his quest to vanquish the corruption by giving him advice, he chooses not to use his powers to aid him/her for they are too terrible and mindbreaking for mortal minds. His purpose in doing this is not clear, perhaps he is at war with the other elder gods of Terraria and using the player as a means to an end, allowing him/her to do all the heavy lifting while he plots in the shadow. Whenever he dies, he revives, often taking on a new name to avoid suspicion. However, the Voodoo Doll is one of his many life sources, taking the form of its current appereance. If the player holds it, The Guide's loses his invulnerability and can be killed, The Guide doesn't care, as he can always come back. But if the player destroys the doll by throwing it into the fires of the Underworld... The Guide's true form, The Wall of Flesh, emerges and attacks the protagonist, enraged by the destruction of his essence by the hands of its own herald.
After The Hallow appears, the efforts of the lifeforms of The Corruption switch from random destruction.Not many people realise that once The Hallow appears, it's just as rampantly infectious as The Corruption. We just tend to not notice it because it's pretty. But look at it from the point of view of the creatures of The Corruption - Not only is the weird blue grass stopping the growth of their home, it's actually pushing it back. This could, if left unchecked, result in the end of life as the corrupted creatures know it. It gets locked in a bit of a stalemate, but...suppose if some adventurer went in and started helping the blue grass's growth...
The Wall of Flesh was the world's personification of balance.Could it be that the Wall of Flesh was trying to protect the overworld from both forces, seeing them as a plague? While the Hallow was easily wiped out, the Corruption had enough power to linger, heavily restrained by it's surroundings. When summoned by sacrificing the Guide, the Wall of Flesh attacks, trying to preserve itself and the balance of the world. Once slain, it drops items that empower you, as if asking you to take it's place as the medium between good and evil. Hope you're up to the task.
Hard Mode is the Player redeeming themselves.You get a lot of equipment pre-hardmode that seems evil (Demon/Necro/Molten). Maybe spreading the Hallow, and making Cobalt, Mythril, Adamantite, and Hallowed equipment is your way to atone?
The Goblins are well-intentioned extremists out to keep the player from destroying the world.The goblins are generally content to completely ignore the player and let them go about their business... right up until the player starts trying to unleash the Eater of Worlds. This causes them to take notice of the player's activities and they start attacking them and their supporters to try to stop them from unleashing the Eater. If they fail, they try to keep up the pressure to hinder the player's goal of destroying the Wall of Flesh and releasing the spirits of light and darkness, which would make the Overworld virtually uninhabitable to anything that isn't a Hallow or Corruption creature. Even if they fail then, they'll keep attacking, often futily, to try and get rid of the player so they can try to re-bind the spirits and make the world safe for regular creatures once again. The Goblin Tinker is evicted for not agreeing with their extremism, and in turn joins up with the player once freed to try to thwart them.
The Hallow is exactly the same entity as the Corruption.The only difference is that the Hallow is well-fed. The Corruption feeds on souls and gains power from them, but most of the souls and spirits were locked away in Hell, with The Wall of Flesh as their guardian. When this happened, the Corruption was greatly weakened, feeding off scraps of souls contained in the Shadow Orbs, and weak enough to be held back by rock and sunflowers. Without the souls, the creatures of the Corruption are forced to make do with consuming physical bodies without being able to take their souls. This allows them to grow bigger, but this barely increases their strength. The largest of the Devourers, the Eaters of Worlds, mostly stay in hibernation without the souls they need to sustain themselves, but when Shadow Orbs are broken, the released souls congregate around the player as they have nowhere else to go. When this congrgation of souls becomes large enough, an Eater of Worlds goes to consume them and fight the player in the process.
The player character is a third force like the Corruption and Hallow, but in human formThe Corruption and Hallow are both powerful and evil forces dedicated to becoming more powerful and taking over the world, and halt each others' progress. The player character will clearly do anything to become more powerful (via increasing their maximum health and mana, and finding/equipping better and better equipment), including killing a man in order to summon an Eldritch Abomination just to ruin the world enough that better ore and items will appear. The Wall of Flesh was holding you back as well (though to a lesser degree), and killing it allows all three forces to reach their full potential; the Corruption and Hallow can spread more and get powerful monsters, and the player can get their best gear and items. You halt the Corruption and Hallow just like they halt each other, by placing blocks they cannot infect and purifying/corrupting them with powders and seeds. The halt your progress with their difficult to mine blocks and dangerous monsters. Youy presence changes the landscape about as much as them; they fill the world with either thorns and purple grass or rainbows and turquoise grass, while you fill the world with buildings made of bricks, ore wood, and other blocks. Instead of merely changing the plant and animal life of the area like the Corruption and Hallow do, you change the basic shape of the land; destroying or building entire hills and lakes. The three forces are not evenly matched; the Hallow is weaker than the Corruption, due to its monsters; Hallowed monsters are not only weaker, but they don't have their own version of the Corruptor, which can spit slime that can turn other grass into Corrupt grass, including changing Hallowed grass. This is why there was no Hallow before Wall of Flesh was defeated; only you and the Corruption. The Player Character's strength relative to the other two is of course based on the skill of the player themself; it is theoretically possible to completely overpower both if the player is willing to spend enough time destroying every corrupt/hallowed block, or the world will be almost completely overrun if the player does not know how to stop them, but much more likely is that the three forces will be locked in a stalemate, with the player able to stop the Corruption and Hallow from spreading past certain points, and building within the area that is not corrupted/hallowed.
The Corruption/Hallow are equal, but not opposite.The Hallow, besides being colourful, isn't much different from the Corruption. It takes over your world, destroying biomes besides itself, having strong monsters, and the trees don't drop acorns, preventing further growth. Think before you turn your world to hardmode...
The Terraria!'Verse is another galaxy.Originally, it was colonised by the Ancients, millennia ago. All was fine, until they awakened the Corruption, which then spread to every planet in this galaxy using the Stargates, forcing the Ancients to retreat to their spaceships, destroy the Stargates on those worlds, and drop down the Shadow Orbs, which are really tracking devices for weapons that fire incredibly large meteorites at where the Shadow Orb was smashed. Unfortunately, like everything else the Ancients did, that went wrong, and the Shadow Orbs didn't give the proper targeting data. So they sent down the Player, to try and activate the Orbs, which would allow the Ancients to wreak flaming havoc with their weapons, occasionally sending down a piece of technology here and there, to help you out in your quest. What they didn't count on was that the planets had their own security systems in place, set down by an even more ancient race. This was the Wall of Flesh, which kept the Corruption relatively in check. When the Player defeats that, the security systems would go into overdrive, creating the Hallow to attempt to stop the Corruption. However, without the security measures put in place by the Wall of Flesh, the Corruption grew even wilder, and spontaneously generated from nothing. TL;DR - The Ancients colonised another galaxy, woke the Corruption up, which spread to all the other planets in that galaxy, so they sent down the Player, while giving him/her amazing technology to help this. The Wall of Flesh is a security measure set up by the even more ancient race that created that galaxy in the first place, and when defeated, stops focussing on controlling the Corruption, and releases the Hallow to control it.
The monsters are formed because of a god/goddess's emotional repression acting out by using his powers.You character, or characters, even if not directly influenced/summoned by him, is a representation of the pressure exerted on the god's psych. You go around, and act either destructively or only to recreate the world. Corruption is caused by the god's anger/regret. Gods, being proud creatures, tend to repress such emotion as it doesn't paint them as perfect. The eaters are doubt, slowly nibbling at him. The chasms are his depressions/mental scars. Things the god did that left a very deep impression on him, such as getting told that they would never be with someone they want by that person, or killing somebody blindly only to find out that they were huge supporters of them beforehand. The shadow orbs collect in response to suppressed memories, not repressed by put into a manageable size while still being acknowledged. Breaking them represents forcing them to become unsuppressed, but seeing as we are not a Psychonaut and thus not in the god's mind it has no real effects other than materializing an item from the memory, the gun representing power or struggle or the thorn being hurting or killing somebody. The eater of worlds attacks because it come into being as a large representation of doubt, so breaking would key to to think that the host is getting depressed, and trying to feed on it when in reality it's just attacking a person. deep underground represents anger, going from "I'm annoyed but can ignore it" to "I'm going to ***ing rip you in half!" In hell, the demons are manifestations of anger, where voodoo was made of anger concentrated at someone, rather than a group, and as the guide was the first one there, apparently, he was the sculpt for the doll. Throwing the doll in summons the wall of flesh because the doll burns up right away, rather than a problem solved the power assumes that it was someone who escaped punishment unharmed. Being the key for "failure", it summons the wall of flesh as the god's full anger. The wall of flesh is the god's shapeless anger. Attacking you because of spite, but because like all the other large bosses it is still attached to the god's psych. When you kill it, the god's power shifts feeling such a sudden change, and it goes to trying to suppress both his good and bad emotions, getting a quick glimpse at what his suppressed anger looks like. That's why hard mode comes in, because the god suddenly starts releasing an influx of magic with his new mental state, let's assume they got drunk when they made the decision. The hallow becomes the suppressed good emotion, but because it's still suppressed the creature that spawn from it, normally hopeful, are angry at being locked away. Blood moon is a moment of emotional stress, taking place over the whole night. Shadow alters are suppressed want/lust. Breaking them releases the feeling that will soon affect metals making more magical one. Sky towers are pride, good items held high above all else. biomes were part of the natural world, and not part of it. Monsters represent forms of stress, such as trying to remember something. The NPCs are other people who happen to come to the place. The sunglasses are so awesome that the god feels need to make the sun acknowledge this.
The creatures of The Hallow used to be gentle and mild around humans before they and their biome dissappeared from the world.A long time ago, The Hallow was a powerful and mystic enviroment which welcomed travellers and offered them susteinance, but it was then exploited, erradicated and bound to The Wall of Flesh for all eternity, an attempt by those who came before to obtain more mahgical power. The player then frees it, but it doesnt act grateful torwards the player for helping it. The Hallow's previous experience made it lose all trust on humanity, and now responds to your mere presence with merciless hostility
The Guide is the avatar of a god, entrusted with the power to keep the Hallow and Corruption under control.Long ago, two great powers, the Hallow, and the Corruption, clashed for control of the world. Eventually, the people of the world begged for help from anyone, anything. So a third power rose up and attempted to seal the two. It sealed the Hallow first. However, the two powers were mightier than it. By the time it sealed the Corruption, it was weakened to the point where a bit of corruption slipped through the cracks. This is where the guide comes in. The third power, which manifested as a pillar of flesh due to its connection with mortals, chose a worthy human, a knowledgeable man, to be it's avatar. The man was granted immortality, and as long as the two were linked, the Hallow and Corruption could not escape to ravage the world. And so, the man remained alive, safeguarding the world for thousands of years. At one point in time, demonic cultists discovered the secret to his immortality and created magical representations of him which allowed the wielder to slay him. Thanks to the god's powers, the man would reincarnate instantly, and only the fires of hell could break their link. And if the link was ever broken, the world would be in grave danger once again. And then, you, the player, murder the guide in the flames of hell. The god manifests as a last-ditch effort to protect the world, so you kill him just for a bit of treasure. You'd better be stopping the Hallow and Corruption, or the world is doomed and it's all your fault. Good job.
Cthulhu is a cyborg by the events of hardmodeWhere do you think The Twins come from?
Molten, Cobalt, Mythril, Adamantite and Hallow armor are self-regenerating, able to repair themselves over time.Since the "Broken Armor" debuff only lasts about five minutes, there has to be a reason they repair themselves. Which leads to...
The Nurse is an exceptional part-time blacksmith as well.Considering that healing can remove the afformentioned broken armor debuff, she must have a way to work with repairing that self regenerating armor.
Another origin theoryThe terraria world is the result of Human evil manifesting itself as the corruption, and wreaking enough havoc before being stopped by researchers that it collapsed the third dimension, resulting in a 2D universe. The wall of flesh was a bio-engineered monster that was made to consume the energy surrounding the Hallow, a manifestation of the Knight Templar hypocrisy of many "Good" people. It also feeds off of the energies that would give strength to the corruption, and turns these into the spawn of the underworld to protect itself from anything that would be tough enough to challenge it. The sheer evil of [[ What the Hell, Hero? stabbing your guide in the back so you can get ores enrages it]] and causes it to fight against you. The artifacts it gives you are from adventurers who have committed similar atrocities in the underworld and lost, but it drops them in it's dying moments as a passive agressive way to try to condemn you to fix what you've broken.
The Guide is the GuideThe Wall of Flesh is actually Chzo showing up and thanking you for the pain you've inflicted. In fact, all he wants is to share some with you.
The Corruption and Hallow are Sealed Evil and Good In a Can, and the Wall of Flesh is their seal.While the Corruption is continuously trying to break free from its prison, being a force of Chaos, the Hallow had instead taken to biding its time and waiting for someone foolish enough to try and break its seal. Should the Wall of Flesh be destroyed, the seal will also be destroyed, and both forces will be unleashed in their full might upon the world, endangering it and its inhabitants, in which case...Nice Job Breaking It, Hero.
The Hallow and the Corruption can affect humans.I based this off an incomplete fanfic I read. Basically, if a human spends too much time in either biome at once, they become Corrupted or Hallowed. In the case of a Corrupted Human, they would gain flight and the ability to shoot Corruptor projectiles. Basically, they are humans intent on spreading corruption under our very noses, Hallowed humans, on the other hand, are meant to fight Corruption and protect the Hallow rather than spread it. So perhaps your character is Hallowed enough to where you're on Terraria's side, not the Hallow's or Corruption's. You can't be corrupted.
The Twins are malfunctioning,How else do you explain their deranged way of moving?!
Terraria was created by an Ancient Tradition of gods to fight evil.Why are there chests and pots in seemingly random places? They were put there by gods who wanted to help you to fight evil.Why are there hundreds of mobs wanting to attack and kill you? They were sent by evil forces. Why does the Old Man turn into Skeletron? He's an evil spirit who took him over. The gods put him there to rid him of the spirit and test your kindness, diligence, and skills. Bypasssing him results in the gods getting angry and sending Dungeon Guardians after you as punishment. The other bosses(including hardmode ones)are similar, being evil spirits that the gods contained and kept for to get rid of for a later date. Summoning them is a message that you are ready for larger responsibilities. Where did the human NPCs come from?They're actually gods in mortal forms who want to help you and guide you on your quest against evil. The Guide is a god of knowledge, the Nurse is a goddess of health, the Merchant is a god of wealth and trade, the Arms Dealer is a god of war (who prefers guns), the Demolitionist is god of fire and explosions, the Wizard is a god of magic and sorcery, the Mechanic is a goddess of electricity, the Dryad is a goddess of nature, and Santa Claus is a god of generosity. The Goblin Tinklerer, though, is a normal blacksmith and mechanic, and the Clothier was the person the Old Man was before his possession by Skeletron. What is up with the Blood Moons, Goblin Invasions, and Frost Legion? They are manifestations of evil forces trying to corrupt Terraria.The Corruption? Evil forces trying to take over Terraria physically.The Hallowed? Same thing, but with with good forces. Those Demon Altars were temples for evil spirits; destroying them pleases the good gods and blesses your world with "good" (as in those used by good forces) minerals.The Hallowed items are those of the good gods. The Underworld itself is the layer of evil, while higher up is where good forces lay. Your character even knows of all this, but is under an oath of silence and/or can't actually talk. TL;DR Everything in Terraria is under control of either good or evil forces.Your character is a pawn in the triumph against good and evil.Terraria itself is the battlefield.
The corruption is a Necromorph infestation.In Dead Space, the "Corruption" is described as an environment changer, but it hasn't been shown affecting an organic environment. The creatures inhabiting the Corruption in Terraria look like they are rotting, almost as though they have been constructed from corpses. This is because they have. Non-Corruption enemies, as well as the deaths of the player and the NPCs, provide the materials required for Necromorphs. My theory is that Terraria is set a good number of years after Dead Space. Very few humans are left, but technology had advanced so far before then that it even resembles magic. However, most of this has been forgotten and the world has been pushed into a dark age. Eaters Of Souls can fly because they have merged with some form of flying equipment, much like the Necromorphs from the Valor had merged with the Stasis units. The Eater Of Worlds is either very old, or constructed from more bodies than most. The Corruption is buffed when the game enters Hard Mode because the Marker responsible for this has been sealed in the same place as everything else unlocked by the Wall Of Flesh. It is somewhere in space, however, so you can't destroy it and get rid of the Corruption that way.
Plantera is the Gaia's VengeanceUnlike the other hardmode bosses, Plantera is an organic creature. And all it takes to invoke Plantera's wrath is to harm a special little flower in the Underground Jungle. Considering what you've probably done by that time, it's rather horrifying. You probably deserved that, anyway.
Terraria is a small, round planet.What's to say that the other side of the ocean at the side of the map isn't actually the shore on the other side of the map? Maybe with a few miles more ocean in between? The reason why we can't just go from the questionably-east side to the questionably-west side might just be a limitation within the game's programming itself.
Consuming Life Fruit gradually turns the player character into a living godThe 1.2 patch added, among other things, Ichor. The description says it is "the blood of the gods". The Golden Shower spell "sprays a shower of Ichor", which appears as a jet of golden liquid. Now turn your attention to the health meter. It's composed of hearts, which are normally colored red because, well, blood is life and red is its color. Upon consuming Life Fruit, the hearts turn a gold color instead. It's much more than a simple user interface element indicating something about gameplay mechanics to the player, it signifies that the character now has ichor in their veins instead of blood.
Crimson is good, while Hallow is evilThink about it, the above point says that Ichor is making the player a god, and where does it drop? Crimson enemies, Why is the Crimson taking over the Jungle? Because the Ichor Sticklers are low on Ichor, and the Jungle is the only place it grows, thus, the Sticklers need to replenish their supply of Ichor, this is also why you can't get Ichor prehardmode, it hasn't grown in the jungle yet! Hallow can overtake Crimson, which is lowering the supply of Ichor in the world, meaning less players can ascend to god-hood. The Corruption in this case is caused by starvation of Ichor, in which in some worlds, Ichor didn't grow until years later, corrupting the wildlife and driving it crazy. But why does the Crimson's Mobs act hostile to the player? Simple, for a point explained above, the Player is a manifestation of a mix of Good and Evil, in other words, neutral, meaning that Crimson sees you as a force to drain Ichor from the land, while the Hallow sees the player as a force to help the Crimson.
The Corruption has a type of monarchy (Or something like that.)This idea grew to me a few days ago. Basically, the Corruption has a monarchy rule going on, where the biggest Eater of Souls are considered nobles, and are not sent very often to fight the player. However, the smaller ones represent the peasants, and since there are alot more peasants than nobles, they are sent to fight the player Zerg Rush style. As for the Devourers, they are simply the children of the Eater of World that is ruling the colony. The small pits that don't reach the underground chasms are where the small Eaters live, while the bigger ones are where the nobles make their home. The horizontal chasm with the Demon Altars is where the Eater of World lives. However, it does not mind if the player happens to pillage the chasms, and kills his soldiers, because there are so many of them, it seems like there is an infinite amount. However, when the player destroys a Shadow Orb to obtain its loot, it is considered a crime, as the Shadow Orbs are used to mutate willing Eater of Souls into Devourers, and eventually Eater of Worlds. Once the player has destroyed a third Shadow Orb, the king of the colony decides that the player is too dangerous and attacks with all his might. If the player is killed, the king returns to a pacific state unless summoned using Worm Food, or three Shadow Orbs are destroyed. If the king is killed, however, a Devourer puts itself to the radiation of a Shadow Orb, which is harmless to humans, to mutate into an Eater of Worlds. The new king then goes deep underground to sleep. Once the world becomes Hard mode, the biggest Eater of Souls undergo a transformation, which morphs them into Corruptors. However, after this transformation, they can no longer feed on the soil of the Corruption. Instead, they start eating the smaller peasants, which is why you rarely see them in Hard mode. As for World Feeders, they are the children from the king, but instead of a mutation, the king lays eggs, which after being infused with Cursed Flames hatch into World Feeders. The Clingers are a dangerous species of Devourers, and they were sealed away deep underground to prevent them from burning the nobles with their Cursed Flames. The Cursed Hammers are the souls of players who were corrupted by the Demon Altars, and because of this, they seek revenge on anything that comes nearby.
The randomly-spawned Destroyer, Twins and Skeletron Prime were built by an NPC plotting against you.Following the death the Wall of Flesh, a new Guide arrives and finds the corpse of the old Guide in his new home. While the old Guide's death may have been from one of many causes, he also notices that the island houses unusual life forms that have not been seen in hundreds, if not thousands, of years. He pieces together that the Wall of Flesh was summoned beneath this island and unleashed the Hallow and the empowered Corruption upon its destruction. And then he meets the player, the one known on the island for slaying the Wall of Flesh. He finally deduces that the player was responsible for the Wall of Flesh's awakening and, by extension, the old Guide's death. Disgusted at the player's disregard for human life and nature (and fearful of being killed himself should the player summon the Wall of Flesh again for profit,) he plots to rebuild the player's old enemies in stronger, mechanized forms. And with your anvil and his knowledge of pretty much every crafting recipe out there (and maaaybe a few leftover reagents for good measure,) he does just that.