Guide:Arena

Note: Most of the arena designs that are listed below have to be edited in their respective Terrain Preparation sections of their guide, as they are transcluded from these pages.

An Arena is generally an area that the player builds where they can face a Boss or other significant challenge more easily. Each arena can be different for each boss, some consisting of a flat area or multiple layers of Platforms supported with Statues.

General Arenas[]

An arena is better built away from Bases so NPCs won't get hurt or killed. It's better built near the ground, far from Space so there won't be any unwanted Harpy or Wyvern spawns during an important fight.
A typical arena usually consists of multiple long rows of Wood Platforms, or a flat surface on the ground or the air made out of Asphalt Blocks to greatly increase running speed.
Sometimes, the shape of the arena depends on the Boss or Event and how the player decides to fight it. Traps and Lava can be used to easily kill enemies from Events, while certain bosses like King Slime lack the ability to attack through solid blocks (although as of update 1.3.0.1, King Slime will teleport directly to the player if he gets stuck on blocks).
Placing Campfires, Heart Lanterns, Honey placed in Bubbles and Heart Statues will greatly increase Health regeneration in battle. A Mage may also want to place Stars in a Bottle and Star Statues to regain Mana more easily.
Peace Candles reduce enemy spawn rate, which may help on bigger arenas - however, in many scenarios such as farming events, an increased spawn rate is more favorable.
Water Candles increase enemy spawn rate, which will help when fighting timed events such as the Pumpkin Moon - keep in mind, though, that fighting bosses or untimed events will be more difficult.
You can build a house for your Nurse NPC near your arena. The House should have a Bed, so in the middle of the battle you can use a Magic Mirror or Recall Potions to visit the Nurse and get instant healing. The house is better built away from the arena to prevent the Nurse from being killed.
A Bast Statue can be used to increase defense of nearby players. It is found in the Underground Desert.
Since luck increases damage, it's helpful to place luck increasing items like Garden Gnomes and the corresponding biome's Torches.
Once you have killed Skeletron and had the Mechanic (or on versions prior to 1.4.4, a Mechanical Boss and had the Steampunker) move in, you can buy and use Teleporters to devastating effect. When wired to a Pressure Plate placed above them, you can instantly transport across the arena as soon as you walk on them, greatly increasing mobility. They could also, alternatively, be used to teleport to the Nurse, heal up, and quickly return to the arena.

Advanced Arenas[]

If using the Nurse is something that you are planning to do, create a three block high valid NPC house directly underneath your arena and move in the Nurse. This way, you can still right-click her easily since she is right underneath you and still run right by without having to enter a building that could trap you.
Try building your arena so the center is at your natural world spawn, that way if an event occurs you can easily teleport there by unsetting your spawn point from your bed and using a Magic Mirror or Recall Potion. You will teleport directly to the arena so you can get in the fight right away, and if you die you will respawn right there again. Try combining this with the above strategy so you can respawn after death right at the Nurse to heal yourself the rest of the way.
If you are going to be moving the Nurse into your arena, it is a good idea to move the Arms Dealer into a nearby or adjacent house so the Nurse will be happy. This way, healing from the Nurse will cost much less than if she was alone, and you can easily buy more ammunition from the Arms Dealer if you run out.

Bosses[]

King Slime[]

Eye of Cthulhu[]

This content is transcluded from Guide:Eye of Cthulhu strategies.

EoC arena — A basic arena made for the Eye of Cthulhu.

An arena for the Eye of Cthulhu should be large enough to dodge and maneuver around in. The recommended size is just about the size of the screen, as the boss does not require a lot of mobility.

The simplest arena design consists of multiple rows of wooden platforms to have more room to jump and dodge. As the fight will be at night, add torches to improve visibility. Remember to adjust the distance between platforms depending on your jump height (this is 6 tiles at minimum, depending on which accessories you have), and consider placing some ladders (with platforms or rope) to aid your vertical movement.

Another design is a long, completely flat surface. This allows you to dodge the Eye by running to the left or the right with Swiftness Potions or Hermes Boots.

One of the easiest ways to defeat the Eye is a long, stretch of sand paired with Dunerider Boots. Due to the speed boost gained on sand, it can be used as a surefire way to make dodging the Eye incredibly easy, making the fight trivial itself. A modification possible for this arena is to add long sections of rope. This can make the second phase easier as the Eye's dashing attack can be easy to dodge. It's recommended that multiple columns are made, in the case the player is knocked off the ropes.

Eater of Worlds[]

This content is transcluded from Guide:Eater of Worlds strategies.

EoW arena — Multiple platforms made for the Eater of Worlds fight.

The player must be in The Corruption to summon the Eater of Worlds; moving too far away from the biome during the battle will cause it to flee.

The Eater of Worlds is a very large Worm enemy, so dodging it may prove to be difficult. You should try and fight it on the surface instead of the underground as the caves will make it hard for you to dodge, but the Eater of Worlds summons extra attacks if you decide to fight it on land. If you are summoning this boss by breaking Shadow Orbs, be sure to provide yourself a quick and safe escape back to the surface where your arena will be. A room with a Bed next to your arena can let you teleport there easily, but be careful that the path from orb to arena does not go through any non-Corrupted areas (lest the boss despawn). When making your arena on the surface, you have some options:

In Normal mode, make it fairly tall, thin, and easily climbable with many Platforms. That way, not only you can see it coming, but this will force it to climb in a relatively straight line, leaving large portions of its body exposed, and vulnerable to piercing attacks.
In Expert mode, due to the frequency of the Vile Spit attack, the Eater of Worlds will become much harder to dodge. Arenas built on the surface make dodging the attacks easier, but they come at the cost of increased movement and attack speed from the boss. Multiple wide platforms are normally sufficient for the fight, but you can enhance the arena by adding walls to prevent normal enemies from spawning.
Whichever option you choose, make sure the arena doesn't go too high. If it goes too high and the Corruption background disappears, the Eater of Worlds will start despawning.
It's also not recommended to build your surface arena above a valley. While it's still above the ground, the hills on either side will provide higher ground for the Eater of Worlds to get to you and make your arena less effective.
To not get interrupted by Eater of Souls, it's recommended to place an Eater of Soul Banner to minimize their damage. You can obtain one by killing 50 Eater of Souls.

If you don't want to fight the Eater of Worlds on the surface, it's possible to fight it underground instead. If you are breaking Shadow Orbs, hollowing out an entire arena every third orb or escaping to a surface arena may not be practical; you should modify the terrain around you to have a quick path of escape to a space with good horizontal clearance and any hazardous terrain smoothed out or boarded over. Consider placing platforms periodically to provide extra maneuverability.

If you have an Autoswing weapon such as the Falcon Blade or a Katana, you can use a Grappling Hook and hook it to the ground to be able to remain stationary. Alternatively, a Cobalt Shield or an Obsidian Shield can be used to become immune to Knockback. If you happen to have any Shadow armor, it could be useful, as it increases your melee speed. Once the Eater of Worlds has been summoned, begin swinging. As the Eater of Worlds tries to inflict damage by passing through you, the Autoswing weapon will destroy its sections fast and effectively, and the fight will be over fairly quickly. This can also be used as an effective farming technique.

Due to the fact that the minecart does contact damage if its going at a high enough velocity, It could continuously hit the Eater of Worlds multiple segments.

Brain of Cthulhu[]

This content is transcluded from Guide:Brain of Cthulhu strategies.

Your arena will have to be built in The Crimson, because it can only be summoned there. Since the Brain of Cthulhu spawns as soon as you smash a third Crimson Heart, you're likely to be in a very enclosed area when the fight begins. This can lead to you being swarmed by the Creepers and getting overwhelmed. This can be avoided by preparing the chasm's main chamber as an arena beforehand, and choosing which Hearts to break first:

For the first two, pick the least convenient hearts (distant, above the main chamber, underwater, etc).
For the third, pick the closest to the main chamber, toss a Bomb or another explosive, and quickly go to your arena while it falls.

If you have access to the Dryad, purchase several stacks of Purification Powder and completely convert the main chamber so that there is no Crimstone Block exposed to air, which prevents you from needing to deal with other Crimson-based enemies during the fight, although standard Underground enemies may spawn in their place. Set up several rows of platforms all the way across the central chamber, close enough that you can jump up to the next platform, and light up everything.

If summoned with a Bloody Spine, then the arena can simply be made in the Surface, however, do not make it very tall, as jumping too far above it will be considered exiting the Crimson, causing the Brain of Cthulhu to despawn. If you have already prepared the central chamber as an arena for a prior fight, use the Bloody Spine there to avoid a despawn.

The Brain Of Cthulhu is unique in the way it reacts when you die. Unlike every other boss, The Brain Of Cthulhu does not despawn upon your death, rather it keeps ramming into the spot you died. You can use this to your advantage by using Purification Powder to clear out a small area to make a basic house. Then if you place a bed inside, you have a respawn point in the main chamber. Now, there is virtually no consequence to dying in the fight, as you can keep respawning and continue the battle. Note: as of 1.4 this no longer occurs.

Queen Bee[]

Skeletron[]

Wall of Flesh[]

This content is transcluded from Guide:Wall of Flesh strategies.The Wall of Flesh benefits from having an arena prepared more than other bosses.

The simplest arena is a long bridge of about 750-1000 blocks with some space above it for the player to maneuver. Placing the player out of danger from falling into lava and ensuring that they can keep a steady attacking pace allows the fight to be faster and easier. Players may also wish to place lights and make holes on the bridge to drain Lava from Lava Slimes or equip Royal Gel ; alternatively, Obsidian Platforms, stone brick platforms, or Planter Boxes can be used, as they do not break when contacting lava, and the materials to make the former two can be obtained in bulk by demolishing the Ruined Houses, or by collecting stone that you've mined throughout the game. Remember that the ash tree biome on the very edge of both sides of the world exists.

However, one can skip the whole terrain preparation process by consuming Water Walking Potions or wearing Lava Waders instead. In 1.4, the Terraspark Boots may be preferable. Do note that it is possible to get stuck in places and houses, so it is recommended to mine or bomb problematic areas out while exploring the Underworld before hand. This is not recommended for Melee users however due to the low range of their weapons.

Note that Underworld map generation tends to place Ruined Houses towards the middle third of the map, leaving the eastern and western wings mostly clean.

The Wall of Flesh begins its attack from whichever side of the Underworld's map edge you're closest to. This allows you to control its direction of approach. Fight in the direction you're most comfortable with.

Killing the Wall of Flesh will generate a bricked-in treasure box above your bridge. The bricks can serve as kill-markers, but they may interfere with movement if your next fight runs close to that spot. These bricks delete anything where they want to spawn, including lava, shimmer, and other blocks.

Alternatively, you can build the arena with Minecart Tracks, since you can keep a safe distance with a Minecart with decent speed. However, keep in mind that jump mobility is more limited when using Minecarts.

While tedious, risky, and generally not worth it, you could use the Superheated Blood Mount to collect all the nearby lava. However, it does require a lot of mining and setup, and it is generally much easier to just use accessories, potions and other items that provide invulnerability against lava and/or fire.

On the 05162020 seed, due to the large lava lake making up the middle of the Underworld, Water Walking Potions, Lava Waders, or the Superheated Blood Mount can be used to bypass terrain preparation.

The Destroyer[]

The Twins[]

Skeletron Prime[]

This content is transcluded from Guide:Skeletron Prime strategies.As with all bosses, an arena made out of Wooden Platform or Minecart Track greatly increases your mobility, and it will also moot the Prime Cannon. You will want several rows of Platforms, each around 50 or so blocks long. The platforms should be suspended off the ground to prevent the Prime Cannon's grenades from detonating too close to you. A solid ceiling should be avoided since Skeletron Prime will often retreat a fair distance when not using his spinning attack. It is also best to use frozen slime blocks as they keep the mobility of any speed enhancements.

Plantera[]

Golem[]

Duke Fishron[]

Lunatic Cultist[]

This content is transcluded from Guide:Lunatic Cultist strategies.A basic arena with some rows of platforms will suffice. If the player made an arena for Skeletron, they can reuse it here.

Moon Lord[]

Dungeon Guardian[]

This content is transcluded from Guide:Dungeon Guardian strategies.

The first option is simply use the whole map, by using Gravitation Potions to move around. You will fall faster than it and you can move diagonally to go even faster.
The second option is a very long Skybridge. You will be equally fast as the Dungeon Guardian when running horizontally and jumping with wings. If you want to outrun it make a diagonal skybridge or build the skybridge out of Asphalt.
The third option is to simply use a good pair of Wings or a flying mount such as the Cosmic Car Key, Witch's Broom (Expert Mode only) or Shrimpy Truffle with a clear, open space.
The fourth option requires a rail system that goes in a circle, using a fast Minecart (Using mechanical Minecart is more useful) or Booster Tracks. This can also be automated with Traps, such as Spike Ball or Spear Traps within the rail circle of with summons and a Star Wrath.
The fifth option is to set up a Hoik loop. As the Dungeon Guardian spawns use a recall potion to get to a spawn point set up near the Hoik loop and mount it. If timed correctly, you will loop around fast enough to make the Dungeon Guardian constantly change direction, and, as a result, simply spin in tight circles in the center of the Hoik loop.

To reliably "summon" the Dungeon Guardian, it is recommended to dig a straight shaft down from outside the dungeon. The Depth Meter or any of its upgrades are recommended for this.

If the player has access to the Mechanic and Steampunker it is possible to build a Teleporter arena (example). This can make the fight dramatically easier, especially if the Teleporters are automated with Timers. As the Mechanic is found in the Dungeon it is required for the player to bring materials from a world where Skeletron has already been defeated.

Invasions[]

General Invasions[]

Invasion events such as the Goblin Army, Pirate Invasion and Martian Madness can only be fought near the Spawn, or somewhere close to an NPC.

Before starting an event, make sure NPCs are protected, otherwise they will be attacked and possibly killed during the fight. Placing a block in front of a Door will prevent enemies from forcing them open and killing the NPCs.

If defended properly, the events can then be easily fought on a player's Base, using the Houses built as cover. Since most enemies from invasions lack the ability to attack through walls, they can be easily killed while standing above them in an enclosed room. However, make sure to have an exit ready for when the enemies that can attack through blocks spawn.

Old One's Army[]

This content is transcluded from Guide:Old One's Army strategies.

Before facing the event, making a completely flat arena works very well. If an enemy's path to the Eternia Crystal is blocked, it will phase through obstacles, so trying to stop their progress with blocks won't be very effective. Building the floor with Asphalt Blocks will greatly increase movement speed. Using Potions is always a good idea, while it is also good to place Campfires, Heart Lanterns, Honey and Heart Statues to survive for longer. When fighting Tier 2 and 3, building a ceiling above the Eternia Crystal will protect it from Kobold Gliders, since they explode on contact with blocks.

Build a raised platform 20 blocks off the ground, halfway between the Eternia Crystal and the expected portal location. Placing Flameburst Towers on these platforms will allow them to target flying enemies more easily, which can reduce swarming of the Crystal in later waves.

Placing a vertical wall behind the spawning points of the portals will allow you to effectively cover both sides of the arena with bouncing projectile weapons like the Water Bolt and Pulse Bow. It may also be a good idea to build houses for competent combat NPCs like the Princess or Pirate behind the portals, so they can help kill enemies without any danger to themselves.

Moon Events[]

Moon Arena — Example of an arena, making heavy use of Traps. Note that on higher difficulties, Traps are hardly useful.

The Pumpkin and Frost Moons are much easier to handle with the proper arena.

A flat surface about 168 blocks wide (See NPC spawning) will focus all spawns on the arena. Above it there should be a long platform of the same width, high above the ground in order to keep grounded enemies out of reach.

Since the player will mostly focus on the Bosses on the later waves, Lava pit and Traps may be helpful to take out the weaker enemies more easily. However, on higher difficulties the Traps' low damage is practically useless against the higher-health enemies, making them almost a liability due to the invincibility frames they provide and the risk of being hit by them and taking massive damage in the process.

It's also a good idea to make a room with a Bed near the Arena, so in case of death you can quickly get back to it.

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