Guide:Walkthrough

When progressing through Terraria, many players can be unsure of what they should do next and where they can go. Terraria is a open-ended game, where areas are only locked by your level of equipment. This progression guide is designed to provide a loose idea of where they should go for these players.

=The Surface=

New players should refer to this guide: Getting Started

 Biome: Forest

Monsters: Green Slime, Blue Slime, Purple Slime, Pinky

Monster Drops: Gel

Notable Resources: Copper, Iron, Mushroom, Daybloom

Chest Contents: Aglet, Blowpipe, Spear, Wooden Boomerang, Glowstick, Throwing Knife, Bottle

Recommended Equipment: Starting equipment

Recommended Life: 5 hearts

All new worlds will spawn players in the forest biome. This biome has the weakest monsters in the game.

The first thing to do when starting a new world is build a shelter. Begin by collecting building materials, such as wood or stone. It is recommended that the shelter include a Table, Chair, a Torch, and walls. This will ensure that the Guide makes this shelter into his house, and will not wander out at night.

If it is still daytime when the shelter is finished, explore the immediate area. Iron can usually be found nearby, and can be used to obtain an early Anvil. Copper can also be found, which is useful for making a Copper Hammer, Copper Bow and Copper armor if an anvil is available. Return to the shelter before the sun goes down. The player may want to arm themselves with a Wooden Sword and Wooden Bow.

 Biome: Night

Monsters: Zombie, Demon Eye, Corrupt Bunny (Blood Moon only), The Groom (Blood Moon only)

Monster Drops: Shackle, Lens, Black Lens, Bunny Hood (Blood Moon only), Top Hat (Blood Moon only)

Recommended Equipment: Iron

Recommended Life: 8 hearts

Zombies and Demon Eyes will spawn on the surface at night, regardless of the biome. They are much stronger than the monsters in the forest biome. Caution is advised.

It is recommended to stay inside at night. The monsters that come out at night can be very difficult for a new character. A bold player may be able to make a substantial amount of money by killing these monsters. This can be very high risk, however, as it is easy to get overwhelmed. Zombies can "stack" on top of each other, making it look as if three or four zombies are only one. Unsuspecting players may try to kill the "single" zombie at their door, only to find that there are actually several more than they can handle.

Many players will find it boring to sit still in a shelter for the whole night. Mining in a cave can be a viable alternative. Fewer monsters will be able to find their way into caves, and they tend to be easier to deal with inside. Mining at night can still be risky, however. Monsters can sometimes drop down on the player's head in caves, which can be very difficult to get out of. Avoid mining under off-screen ledges.

A little later in the game there is a chance of a night event occurring called the Blood Moon, which temporarily increases the monster spawn rate - among other things. It is recommended to remain indoors during this time especially for inexperienced players.

Build a Base
For a more in-depth guide on building bases: Bases

Once the temporary shelter is completed, it is time to start on a base of operations. A base can take anywhere from a single in-game day to more than an in-game week to complete, depending on the player's tastes. It is not necessary, however, to build the entire base right away. Waiting to build the majority of the base can be advantageous, as it will allow the player to use the large stock of stone they will end up gathering as a by-product of mining. Regardless of when or what the player builds, it is recommended to build houses for the Guide, Merchant and Nurse, and a space for storage and crafting before progressing.

Surface Exploration
The surface has sparsely distributed iron and copper deposits. It is advantageous to the player to search for these ores. If the player finds enough, the player may be able to craft some new tools and armor before they begin mining. Chests can sometimes be found in the entrances of caves. The items they contain can be very useful for a new character. These chests will spawn in any surface biome but the treasures they contain are listed with the forest biome.

It is highly recommended to stay in the forest biome. The other surface biomes are mid-game biomes, and will be too difficult for a new character.

=The Underground=

For a more in-depth guide on mining: Mining Techniques

Once a satisfactory shelter has been completed, the player should begin mining. There are multiple methods of mining, each with its own advantages and disadvantages. Digging a mine shaft can allow the player easy access to the deeper areas of their mine. Another popular method is to explore the caves and tunnels that generate naturally. When a player reaches a dead end in a cave, they can find other caves using light from torches or other tools, a technique called "cave hopping". This method can yield more rewards than the shaft method, but it can be harder to enter and exit this type of mine. Many players will use a combination of the two methods to suit their current needs.

 Biome: Underground

Monsters: Blue Slime, Red Slime, Yellow Slime, Pinky, Blue Jellyfish, Giant Worm

Monster Drops: Gel, Glowstick, Whoopie Cushion

Notable Resources: Copper, Iron, Silver, Gems, Glowing Mushroom, Blinkroot

Chest Contents: Band of Regeneration, Magic Mirror, Angel Statue, Cloud in a Bottle, Hermes Boots, Enchanted Boomerang, Jester's Arrow

Recommended Equipment: Starting equipment

Recommended Life: 5 hearts

The underground can be identified by its background (pictured to the right). It is the first layer below the surface. Copper and Iron deposits can be found in this layer. Silver and Gold can also be found, though less frequently and only much deeper down. Glowing Mushrooms can also be found, though infrequently at this layer.

The player should focus on finding copper and iron while in this layer. It is recommended to have full iron armor and silver weapons before proceeding to the next layer. The player should also try to find two or three Life Crystals while at this layer.

When the player reaches the caverns, they should build a fourth NPC house. This should allow them to get the Demolitionist. It is recommended to buy the Mining Helmet at about this point, or very soon after. A player may wish to opt out of getting the mining helmet, however, if they found an early source of Glowing Mushrooms, and they wish to use Shine Potions instead.

 Biome: Cavern

Monsters: Black Slime, Mother Slime, Baby Slime, Pinky, Giant Worm, Skeleton, Cave Bat, Blue Jellyfish, Piranha, Undead Miner, Tim

Monster Drops: Gel, Whoopie Cushion, Hook, Wizard Hat, Robot Hat

Notable Resources: Copper, Iron, Silver, Gold, Demonite, Gems, Glowing Mushroom, Blinkroot, Lava

Chest Contents: Band of Regeneration, Magic Mirror, Angel Statue, Cloud in a Bottle, Hermes Boots, Enchanted Boomerang, Jester's Arrow

Recommended Equipment: Iron

Recommended Life: 8 hearts

The caverns can be identified by their background (pictured to the right). It is the second layer below the surface. Copper, Iron, Silver and Gold can all be found frequently in this layer. Glowing Mushrooms can also be found more regularly in this layer.

In this layer, the player should focus on upgrading to Silver equipment, then Gold equipment. They should also try to find a hook for a Grappling Hook, and as many Life Crystals as they can find, at least three or four. This layer can be very dangerous for an under-geared player. The player should not attempt to progress through this layer if they have not yet obtained Iron equipment. Regardless of what equipment is currently available, it is recommended to bring lots of potions, including a few Ironskin Potions.

Avoid mining too deeply in this layer at this point in the game. The next layer after the caverns is the Underworld, which is a mid-game area. If the player mines too closely to the Underworld, Underworld monsters will begin to spawn. Underworld monsters can be very difficult to deal with, even with a mid-game character. If the player finds themselves being attacked by Fire Imps, it is highly recommended to turn back. As a rule of thumb, avoid mining down any further when the first lava pools are found.

=The Surface Revisited=

Once the player obtains complete gold equipment many mid-tier biomes open up. These biomes contain alchemy ingredients as well as other treasures. It is recommended to build any NPC houses that have not been built yet. There should be at least seven NPC houses at this time.

 Biome: Desert

Monsters: Vulture, Antlion, Mummy

Monster Drops: Antlion Mandible

Notable Resources: Cactus, Waterleaf

Recommended Equipment: Iron

Recommended Life: 7 hearts

The desert doesn't contain much of interest other than alchemy ingredients. The monsters in the desert are in the lower-mid tier, and can be dealt with using iron equipment or better.

 Biome: Jungle

Monsters: Piranha, Snatcher, Jungle Bat, Jungle Slime, Doctor Bones (night only)

Monster Drops: Gel, Hook, Robot Hat, Archaeologist's Hat

Notable Resources: Moonglow, Jungle Rose, Jungle Spores

Recommended Equipment: Gold

Recommended Life: 10 hearts

The jungle is one of the more difficult surface biomes. Gold equipment is recommended before attempting to explore it.

 Biome: Corruption

Monsters: Little Eater, Eater of Souls, Big Eater, Devourer, Corrupt Goldfish, Piranha

Monster Drops: Rotten Chunk, Worm Tooth, Hook, Robot Hat

Notable Resources: Vile Mushroom, Deathweed, Demonite

Shadow Orb Contents: Ball O' Hurt, Band of Starpower, Musket, Orb of Light, Vilethorn

Recommended Equipment: Gold

Recommended Life: 10 hearts

The corruption is a very difficult biome due to the swarming of Eaters of Souls. Exploring the corruption can be very rewarding, however. Smashing Shadow Orbs can yield very powerful items. Beware though, as breaking three Shadow Orb will result in the Eater of Worlds being summoned. Demonite is found in large deposits in this biome, though a Gold Pickaxe is needed to mine it.

 Biome: Ocean

Monsters: Shark, Pink Jellyfish, Crab

Monster Drops: Glowstick, Shark Fin, Diving Helmet

Notable Resources: Coral

Chest Contents: Breathing Reed, Flipper, Trident

Recommended Equipment: Gold, Gills Potions

Recommended Life: 10 hearts

The Ocean is notable for its alchemy ingredients and chests. Chests found in ocean biomes contain unique treasures. New characters may have problems working in this biome. Without access to alchemy ingredients like waterleaf, finding a source of air can be a major issue.

Eye of Cthulhu
Once the player gains ten or more hearts, it is likely that they will have to fight the Eye of Cthulhu.

Eye of Cthulu has a 1:3 chance of spawning each night if:


 * Eye of Cthulhu has not been defeated in the current world
 * At least one player in the world has ten or more hearts
 * Four NPCs have moved into houses in the world

If the player meets all three of these requirements, they should prepare to fight Eye of Cthulhu. Buy a stack of Shurikens from the Merchant. Build an arena (see the Terrain preparation section in the Guide: Eye of Cthulu strategies). Many players prefer to summon Eye of Cthulhu before these requirements are met, to ensure that they fight the boss on their own terms. To summon Eye of Cthulhu, craft a Suspicious Looking Eye and use it at night.

 Boss: Eye of Cthulhu

Life: 2800

Damage: 15 (First Stage), 23 (Second Stage)

Defense: 12 (First Stage), 0 (Second Stage)

Minions: Servant of Cthulhu (8 Life, 12 Damage, 0 Defense)

Drops: Demonite Ore, Unholy Arrows, Corrupt Seeds

Recommended Equipment: Gold, Piercing Weapons, Hunter Potions, Ironskin Potions, Regeneration Potions

Recommended Life: 10 hearts

Piercing weapons are most efficient on Eye of Cthulhu, as they will damage it multiple times each attack. Melee weapons are not very effective on Eye of Cthulhu as it will usually fly out of reach. In its first stage, Eye of Cthulhu spawns minions and will try to ram the player. When Eye of Cthulhu has less than 1400 life, it will morph into its second stage. In its second stage, Eye of Cthulhu will stop spawning minions, but it will begin to move much faster, and do much more damage with each attack. If the player has Gold equipment and plenty of potions, Eye of Cthulhu shouldn't pose a major threat.

For more information, refer to Guide:Strategies for killing Eye of Cthulhu

Eater of Worlds
After Eye of Cthulhu is defeated, the player should fight Eater of Worlds.

Eater of Worlds will spawn upon smashing every third Shadow Orb in a world. It is also possible to spawn Eater of Worlds using Worm Food. This is not recommended, however, as smashing Shadow Orbs will drop treasures like Vilethorn and Ball 'O Hurt that can help defeat Eater of Worlds.

 Boss: Eater of Worlds

Life: 65 (Head), 150 (Body), 220 (Tail)

Damage: 22 (Head), 13 (Body), 11 (Tail)

Defense: 2 (Head), 4 (Body), 8 (Tail)

Drops: Demonite Ore, Shadow Scale

Recommended Equipment: Gold, Piercing Weapons, Ironskin Potions, Hunter Potions

Recommended Life: 12 hearts

Eater of Worlds has 50 segments. When one segment is destroyed, the two separated sections will become a new worm. Piercing weapons are extremely effective against this boss, as they will damage Eater of Worlds many times. Melee weapons are also effective. It is safer to fight this boss in an enclosed area, because the monsters that spawn in the corruption are noticeably more difficult to deal with in the open.

For more information, refer to Guide:Strategies for killing Eater of Worlds

Smashing Shadow Orbs has a small chance of spawning a meteor somewhere in the world. If a meteor spawns, and a Gold Pickaxe is available, craft an Obsidian Skull and track it down.

 Biome: Meteorite

Monsters: Meteor Head

Notable Resources: Meteorite

Recommended Equipment: Shadow, Obsidian Skull, Dynamite

Recommended Life: 12 hearts

Meteor Heads will constantly spawn when there are 50 or more meteorite blocks in the area, so it is recommended to mine the meteorite as quickly as possible. Dynamite is very effective on meteorite for this reason. A few sticks of dynamite can mine most of the biome singlehandedly, minimizing the Meteor Head threat.

=The Dungeon=

After obtaining some combination of shadow equipment and meteor equipment, the player should explore the dungeon. The Dungeon can be found near the right or left edge of the map. To gain entrance to the dungeon, Skeletron must be defeated. To summon Skeletron, talk to the Old Man in front of the dungeon at night.

 Boss: Skeletron

Life: 4400 (Head), 600 (Hand)

Damage: 32 (Head), 32 (Hand)

Defense: 10 (Head), 10 (Hand)

Recommended Equipment: Shadow or Meteor, Piercing Weapons, Ironskin Potions

Recommended Life: 15 hearts

Like with other bosses, piercing weapons are very effective against Skeletron. Melee weapons are of limited effectiveness, as Skeletron floats out reach for much of the time. Like with other bosses, a player with a large stock of potions shouldn't have too much trouble with this boss.

For more information, refer to Guide:Strategies for killing Skeletron

After Skeletron has been defeated in a world, players should be able to enter the dungeon unimpeded.

 Biome: Dungeon

Monsters: Angry Bones, Big Boned, Short Bones, Blazing Wheel, Cursed Skull, Dark Caster, Spike Ball, Dungeon Slime

Monster Drops: Bone, Golden Key

Notable Resources: Switch, Chain Lantern, Life Crystal, Water Bolt

Chest Contents: Aqua Scepter, Blue Moon, Cobalt Shield, Handgun, Magic Missile, Muramasa, Shadow Key

Recommended Equipment: Shadow or Meteor

Recommended Life: 15 hearts

Monsters respawn very quickly in the dungeon, so it can be difficult to progress. Movement enhancing items, such as the Grappling Hook or Cloud in a Bottle are highly recommended. Many of the surfaces in the dungeon are covered in damaging spikes, making it difficult to progress without some sort of movement aid.

It is recommended to get all of the treasures in the dungeon, as they are all useful for further progression. Water Bolt can also be found on bookshelves (pictured). The dungeon has a substantial amount of Life Crystals in it, making it easy for a player to reach maximum life by the time they are finished with the dungeon. Also note that Hidden Island chests are locked with the golden keys obtained in the dungeon, so after you have finished it is advisable to keep at least three keys to open them.

 Biome: Floating Island

Monsters: Harpy

Monster Drops: Feather

Notable Resources: Silver, Gold

Chest Contents: Shiny Red Balloon, Starfury, Lucky Horseshoe

Recommended Equipment: Gold, Gravitation Potions

Recommended Life: 10 hearts

Although possible, there is little point in visiting floating islands until you've obtained Golden Keys from the Dungeon to unlock the Gold Chests there. The easiest way to locate floating islands is to fly across the map using Gravitation potions at certain heights with the aid of a Depth Meter. Floating islands are typically found at 500-600ft on small maps, 500-800ft on large ones.

Harpies spawn around floating islands if not in the middle third of the map. Harpies are less dangerous since 1.1.

=The Underground Jungle=

After completing the Dungeon, the player should next go to the Underground Jungle. The Underground Jungle can be found by mining directly downward from the surface jungle.

 Biome: Underground Jungle

Monsters: Hornet, Little Stinger, Big Stinger, Man Eater, Jungle Bat, Piranha

Monster Drops: Stinger, Vine, Hook, Robot Hat

Notable Resources: Moonglow, Jungle Spores, Jungle Rose, Nature's Gift

Chest Contents: Feral Claws, Anklet of the Wind, Staff of Regrowth

Recommended Equipment: Shadow, Meteor, or Necro; Dungeon weapons

Recommended Life: 15 hearts

The underground jungle is the second-most difficult biome in normal mode. An improperly geared player will have a difficult time surviving in this biome. Much like the corruption's Eater of Souls, the Underground Jungle's hornet will persistently swarm the player, while shooting poisonous stingers at them.

The risk of exploring the Underground Jungle can pay off. Some of the best items pre-hardmode can be found in or crafted from items in the Underground Jungle, such as Ivy Whip or Jungle armor.

=The Underworld=

After exploring the Underground Jungle, the player should go to the Underworld. The Underworld can be found covering the entire bottom of the map. It is reached by digging down from the caverns.

 Biome: The Underworld

Monsters: Lava Slime, Hellbat, Fire Imp, Demon, Voodoo Demon, Bone Serpent

Monster Drops: Plumber's Hat, Demon Scythe, Guide Voodoo Doll

Notable Resources: Hellstone, Fireblossom, Hellforge, Demon Torch

Chest Contents: Dark Lance, Flower of Fire, Sunfury, Flamelash

Recommended Equipment: Shadow, Meteor, Jungle, or Necro; Jungle or Dungeon weapons; Obsidian Skull; Water Walking Potion, Obsidian Skin Potion, Night Owl Potion

Recommended Life: 15 hearts

The best items pre-hardmode can be found in or crafted from items found in this biome. The player should try to locate Shadow Chests, opened with the Shadow Key found in the Dungeon.

Be very careful when killing Voodoo Demons, particularly from range, as their voodoo doll can then drop into lava, summoning a very unwelcome Wall of Flesh!

Although the Underworld is theoretically the most difficult biome in normal Terraria, mining Hellstone is reasonably easy and safe and can be done with fairly low-level equipment, especially with the aid of Obsidian Skin potions and Obsidian Skull. Water Walking potions are also very helpful, allowing you to walk on lava, and Night Owl potions do a great job of lighting up hell.

Ironically, Hell becomes one of the safest biomes in Terraria in hardmode.

Wall of Flesh
Defeating Wall of Flesh will activate hardmode. There is no turning back once hardmode is initiated in a particular world, so make sure you are satisfied with your current equipment and other preparations before initiating hardmode. For example, you may wish to scout out Demon Altar locations, and dig a quarantine around your base (discussed in the hardmode section.) Having the best possible equipment (Hellstone, Night's Edge) going into hardmode will make your time far easier.

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Life: 8000 (Eyes, Mouth), 320 (The Hungry)

Damage: 11-15 depending on health (Eye laser), 50 melee (Eyes, Mouth), 30-75 depending on health (The Hungry)

Defense: 12 (Eyes, Mouth), 10-40 depending on health (The Hungry)

Drops: Pwnhammer + one of: Breaker Blade, Clockwork Assault Rifle, Laser Rifle, Warrior Emblem, Ranger Emblem, Sorcerer Emblem

Recommended Equipment: Molten recommended (Shadow or Necro viable), ranged weapons such as Phoenix Blaster and Demon Scythe, Spectre Boots

Recommended Life: 20 hearts

To summon the Wall, you must drop a Guide Voodoo Doll dropped by Voodoo Demons into the lava in the Underworld. It will spawn just outside of the screen in the direction closest to the world border and start moving slowly towards you, speeding up as its health decreases. Due to the WoF's tongue ability and The Hungry's short range, a ranged weapon is highly recommended. AoE attacks such as Demon Scythe or Hellfire arrows are very effective in clearing out the initial pack of Hungry. Flails and Spears are also viable for this fight.

Preparing an arena for this fight is also recommended: a long, straight land bridge 500+ blocks long is ideal.

Once Wall of Flesh is defeated, you will receive a message which says "The ancient spirits of light and dark have been released." You have now entered Hardmode.

=Hardmode=

Hardmode introduces new aspects to your world and makes survival a challenge again. Some of the key changes in hardmode are:
 * A completely new biome, The Hallow (and accompanying Underground Hallow)
 * New, harder monsters in many existing biomes (note: the Forest, Snow, Meteorite, Ocean, Dungeon, Jungle, Underground Jungle, and Underworld biomes remain unchanged, by day.)
 * The original 3 bosses return
 * Demon Altars can be broken by the Pwnhammer, creating new hardmode ores to craft new equipment
 * New items and drops, including at NPC stores
 * Two diagonal stripes of Hallow and Corruption extending from the Underworld to the Surface in a v-shape are created immediately following the first-time defeat of Wall of Flesh
 * The Corruption and Hallow can spread through stone, sand, and grass (but not each other), and can convert blocks up to three squares away. Additionally, the Corruption can corrupt the Jungle by corrupting jungle grass and changing mud to dirt (at a reduced rate), something the Hallow cannot. Sunflowers can also no longer contain the corruption and will be uprooted by it.

Quick overview on containing the Hallow/Corruption:
 * The practical consequence of entering Hardmode is that the Hallow and Corruption will inevitably spread and claim much of your world unless extreme measures are taken (refer to Guide:Containing the Hallow/Corruption.) This is because the underground layers are mostly composed of dense stone, which the Hallow/Corruption pass through quickly, and the V-stripes means the initial front already extends from the top to the bottom of the map. Note that this is not necessarily a bad thing, as there are many rewards to be had from the Hallow and Corruption.
 * If you do wish to contain the Hallow/Corruption, digging a shaft 3 blocks wide effectively halts its progress underground. There are a few caveats: above 0ft, Hallow/Corruption can spread more than 3 blocks by their vines/thorns, corruptors' spit creates new corruption any time it lands on corruptible blocks, and breaking demon altars can convert any random block in the world to corruption/hallow, potentially bypassing your quarantine.
 * Below 0ft, even dirt and mud act as a barrier to Corruption/Hallow as grass cannot grow below ground. It is only stone and sand that can spread them there.
 * The Dungeon usually acts as a large natural barrier as it extends from the surface to around the start of hell (a snow biome is another effective surface buffer.)
 * If you wish to "save the jungle," bordering it with Hallow is a potentially good idea as only Corruption can convert the Jungle.

New and Changed Hardmode Biomes
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New Monsters: Possessed Armor, Wandering Eye, Wraith, Clown (Blood Moon), Werewolf (Full moon)

Recommended Equipment: Molten

The night is now harder.

<div style="width: 600px; margin-top: 10px; margin-bottom:3px; background-color: #D4A017; padding: 1em 1em; font-size: 100%; border: 1px outset #717D7D; border-bottom:2px outset #717D7D; border-right:2px outset #717D7D; -moz-border-radius: 15px;"> Biome: Desert (Hardmode)

New Monsters: Mummy, or Dark Mummy + other Corruption enemies (Corrupted Desert), or Light Mummy + other Hallowed enemies (Hallowed Desert)

Monster Drops: Dark Shard (Corrupt Desert) or Light Shard (Hallowed Desert)

Recommended Equipment: Molten

Natural deserts typically don't last long in hardmode. When corrupted or hallowed, they become very similar to their respective biome.

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New Monsters: Corruptor, Slimer, Corrupt Slime

Recommended Equipment: Molten

Corruption now spreads through the world at a fast clip. Corruptors spawn in packs and introduce ranged and far more powerful attacks which spread the corruption wherever they land. On the plus side, the Corruptor's bile is easily blocked by any weapon.

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Monsters: Pixie, Unicorn, Gastropod (night only)

Monster Drops: Pixie Dust, Unicorn Horn

Recommended Equipment: Molten

The Hallow is generated once the player enters hardmode, and is a tough surface biome, particularly at night.

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New Monsters: Wyvern

Monster Drops: Soul of Flight

Recommended Equipment: Mythril or better

Wyverns now spawn on hardmode and are very dangerous even to well-equipped players. It is recommended to obtain hardmode gear before engaging them in combat.

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New Monsters: Toxic Sludge, Digger, Possessed Armor (night)

Recommended Equipment: Molten, Molten Pickaxe

You will notice that the new mobs make the underground quite hostile compared to what it used to be before hardmode.

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New Monsters: Armored Skeleton, Skeleton Archer, Giant Bat, Digger, Angler Fish (water), Green Jellyfish (water)

Recommended Equipment: Molten, Molten Pickaxe

The hardmode caverns are harder than any normal mode biome, and nearly as hard as Underground Hallow or Corruption.

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Monsters: Chaos Elemental, Illuminant Bat, Illuminant Slime, Enchanted Sword

Monster Drops: Soul of Light

Notable Resources: Crystal Shard

Recommended Equipment: Molten at a minimum, Mythril or better recommended

Underground Hallow and Corruption are currently the hardest biomes in Terraria. Mining here can be quite challenging especially due to teleporting Chaos Elementals. On the plus side, dimly glowing crystal shards soon illuminate the Underground Hallow's caverns.

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Monsters: Clinger, Corrupt Slime, Corruptor, Cursed Hammer, Devourer, Slimer, World Feeder

Monster Drops: Soul of Night, Cursed Flame

Recommended Equipment: Molten minimum, Mythril or better recommended

The Underground Corruption difficulty is on par with the Underground Hallow, and is currently tied for being the most difficult biome in Terraria.

Mining in Hardmode

 * Mining the new hardmode ores is the main way to obtain much of the best hardmode equipment.
 * Your first step on entering hardmode should be to break demon altars with your Pwnhammer.
 * Before you even do this, you may wish to kill Wall of Flesh additional times to obtain useful drops. Clockwork Assault Rifle is the 2nd best (bullet-based) gun in the game, and comparable to Megashark. Obtaining the appropriate Emblem for your playstyle is also recommended.

Demon Altars
 * Breaking demon altars generates hardmode ores in your world
 * Breaking your first will give you a message that the world has been blessed with Cobalt. Breaking your second will give you a message that the world has been blessed with Mythril. Breaking your third will give you a message that the world has been blessed with Adamantite. The fourth starts at cobalt again.
 * Demon altars can often be found in rows in the original "deep corruption" at the bottom of corruption shafts (the same places you find shadow orbs) - at about 0ft.
 * Each time a demon altar is destroyed, there is a chance a single random tile of rock in the world will be converted into ebonstone or pearlstone. This will more than likely grow to become a new underground Hallow or Corruption if given enough time.
 * Demon altars generate less new ore as more are destroyed. The second set of altars create 1/2 as much ore as the first set, the 3rd set creates 1/3 as much as the first, and so on. By the time you've smashed 12-15 there will be an abundance of hardmode ores (on a small map.)
 * Breaking a demon altar spawns 1-2 Wraiths which can be deadly for players with Hellstone equipment. As wraiths can only hover above the ground, grappling on to a wall or ceiling can allow you to kill them safely.
 * The Underground Corruption is dangerous for players with normal mode equipment so it is not recommended to hang around after you've finished smashing altars.

Where to Mine
 * You can find the hardmode ores, in order of increasing difficulty, in the Underground Jungle, Cavern, and Underground Corruption/Hallow
 * It is recommended to mine in the Underground Corruption/Hallow if possible, as you will obtain useful drops there, but it can be quite difficult, although possible, with hellstone equipment.
 * If you find it too hard mining in the UC/UH, the Underground Jungle is the easiest and often overlooked. Cavern monsters are much tougher but the high spawn rates and hornet's ranged attacks in the UJ means you can be harassed more in the UJ.

Cobalt
 * You need a Molten Pickaxe to mine cobalt
 * Cobalt can be found from roughly 0ft to the roof of hell - ie the Underground and Cavern depths. It is very common (once many demon altars have been smashed)
 * A Cobalt Drill (45 cobalt ore) should be your first priority.

Mythril
 * Once you have a cobalt drill, you should also begin mining Mythril. Mythril is found anywhere at the same depths as the Caverns.
 * A Mythril Anvil (40 mythril ore), followed by a Mythril Drill (60 ore) should be your first priority.

Adamantite
 * Once you have a mythril drill, you should also begin mining Adamantite. Adamantite is usually found around where lava pools spawn above hell.
 * Adamantite is the least common hardmode ore so it is helpful to have smashed lots of demon altars before searching for it.
 * As Adamantite is usually found in and around lava, Obsidian Skin potions and perhaps Water Walking potions are indispensable. Ironically, lava is your best friend as it can keep you safe while immersed, particularly when in the Underground Corruption/Hallow. A set of Diving Gear is also recommended. Night Owl potions and Spelunker potions can help you to spot adamantite more easily.
 * An Adamantite Forge (30 adamantite ore) should be your first priority

Recommended Mining Gear

 * These recommendations assume you haven't beaten any hardmode bosses yet.

Armor
 * You can mine yourself a set of Adamantite Armor with as little as Hellstone equipment, especially if you stay in the jungle. However, if mining in the Underground Corruption/Hallow, which is recommended, you will want to upgrade to hardmode armors as quickly as possible.

Weapons

Melee:
 * Night's Edge is still effective if you have it, but upgrading to Phasesaber is highly recommended as it is easy to obtain and the 2nd best sword in the game, comparable to Excalibur.
 * Dao of Pow or a hardmode Spear are also excellent.

Ranged:
 * Clockwork Assault Rifle is the 2nd best (bullet-based) gun in the game, and can tide you over until you get Megashark.
 * Repeaters are also excellent, especially against mobs, when combined with high-end arrows like Holy Arrow.

Magic:
 * Magic is a bit weaker, you want to look at Crystal Storm, Laser Rifle, Demon Scythe, and Ice Rod

Accessories

General purpose: Wings or Obsidian Horseshoe, Spectre Boots, Diving Gear, Obsidian Shield, Cross Necklace, Star Cloak, Philosopher's Stone

Melee: Warrior Emblem, Feral Claws

Ranged: Ranger Emblem

Magic: Sorcerer Emblem, Mana Flower

The Hardmode Bosses
<div style="width: 600px; margin-top: 10px; margin-bottom:3px; background-color: #6D7B8D; padding: 1em 1em; font-size: 100%; border: 1px outset #717D7D; border-bottom:2px outset #717D7D; border-right:2px outset #717D7D; -moz-border-radius: 15px;"> Boss: The Destroyer

Life: 80000

Defense: 0 (Head), 30 (Body), 35 (Tail)

Damage: 60 (Head), 40 (Body), 22 (Body - Death Laser), 20 (Tail)

Minions: Probes

Drops: 20-30 Soul of Might, 5-15 Greater Healing Potion

Recommended Equipment: Molten minimum, Adamantite recommended, melee and ranged both feasible, Phasesaber or Adamantite Repeater both strong picks.

Buffs: Ironskin, Regeneration, Soup. Optional: Ale (melee), Archery (repeater), Gravitation, Thorns (only does 1 dmg to Destroyer but can damage/knock away probes), Swiftness

The Destroyer is the hardmode version of Eater of Worlds. The Destroyer is summoned by using a Mechanical Worm at night, meaning the earliest you can fight The Destroyer is when you at least have a Mythril Anvil, and it is quite possible to defeat him as soon as you are able to make one.

The Destroyer is the easiest of the three hardmode bosses, as well as the most rewarding (allows you to make Megashark, arguably the best ranged weapon in the game), and so should be fought first.

The Destroyer is probably best fought using melee weapons, but ranged is equally good. This video demonstrates an easy, straightforward method to destroy the Destroyer.

Unlike Eater of Worlds, the Destroyer does not break into pieces as you kill it, but remains intact until its shared life total reaches 0. As the Destroyer takes damage, Probes drop off and attack you, leaving hearts when they die which help you stay alive.

You need to kill The Destroyer 4 times to make all his drops.

<div style="width: 600px; margin-top: 10px; margin-bottom:3px; background-color: #6D7B8D; padding: 1em 1em; font-size: 100%; border: 1px outset #717D7D; border-bottom:2px outset #717D7D; border-right:2px outset #717D7D; -moz-border-radius: 15px;"> Boss: The Twins

Life: 24000 (Retinazer), 24000 (Spazmatism)

Defense: 10/25 (Retinazer 1st/2nd form), 10/35 (Spazmatism 1st/2nd form)

Damage (Retinazer): 50 melee / 20 laser (1st form), 75 melee / 25 laser / 20 rapid fire laser (2nd form)

Damage (Spazmatism): 50 melee / 25 cursed flame (1st form), 75 melee / 30 cursed flamethrower (2nd form)

Drops: 20-30 Soul of Sight, 5-15 Greater Healing Potions

Recommended Armor: Adamantite-ranged

Recommended Weapons: Megashark/Crystal Bullets

Recommended Accessories: Wings, Spectre Boots, Ranger Emblem, Cross Necklace, Philosopher's Stone, all w/ +4 def or +4% dmg modifiers

Buffs: Ironskin, Regeneration, Swiftness. Optional: Soup, Gravitation, Thorns

The Twins are the hardmode version of Eye of Cthulhu. They are summoned by using a Mechanical Eye at night.

Retinazer and Spazmatism are individual entities with their own HP, and can be killed independently. They will transform into their 2nd form when their hp has been reduced below half (12000hp.)

Generally it is easier to focus down one first before the other: it's recommended to kill Spazmatism first as Retinazer's first form isn't very dangerous.

<div style="width: 600px; margin-top: 10px; margin-bottom:3px; background-color: #6D7B8D; padding: 1em 1em; font-size: 100%; border: 1px outset #717D7D; border-bottom:2px outset #717D7D; border-right:2px outset #717D7D; -moz-border-radius: 15px;"> Boss: Skeletron Prime

Life: 30000

Defense: 25, 50 when spinning

Damage: 50, 100 when spinning (head), 30 melee/40 bomb (cannon), 52 (saw), 45 (vice), 29 melee/25 laser (laser)

Drops: 20-30 Soul of Fright, 5-15 Greater Healing Potions

Recommended Armor: Adamantite-ranged

Recommended Weapons: Megashark/Crystal Bullets, Adamantite Repeater, Star Cannon

Recommended Accessories: Wings, Spectre Boots, Ranger Emblem, Cross Necklace, Philosopher's Stone, all w/ +4 def or +4% dmg modifiers

Buffs: Ironskin, Regeneration, Swiftness. Optional: Soup, Gravitation, Thorns

Skeletron Prime is the hardmode version of Skeletron. It is summoned by using a Mechanical Skull at night.

This is a similar fight to The Twins. The main difference is that instead of transforming, SPrime launches his spinning head attack. During this time, his defense goes up and he tends to protect himself with his arms, so it can make sense to switch to a high damage/piercing attack like the repeater (use jester, unholy, or holy arrows) or star cannon.

For a good demonstration of how to take down Skeletron Prime, see this video.