There are 12 Arenas in total, 3 of which can be found in each region.
Once the player has finished any of the base game faction quest lines, the base game hidden Boss Arenas will become accessible. Access to the Caldera Arenas requires completion of the New Sirocco quest line. Boss Arenas typically require a one-time fee to enter, such as a small amount of a certain item. Some Arenas also require special conditions such as having certain status effects active on the player. Once the player has entered the Arena for the first time, they will no longer need to meet the entry requirement, even if they are defeated on their first attempt.
Upon defeating all the Bosses in the Arena, the player will be able to access a special Ornate Chest which will contain 2 random Relics. These Relics can be used to craft powerful new Weapons and Armor. Each Arena has 4 different Relics which players can receive, and they are guaranteed 2 different Relics on each drop, the same Relic will not be rewarded twice in one drop.
Like all Area Resets, the Arenas will reset after 7 days spent outside of the Arena, and the player can repeat the fights as many times as they wish.
List of Boss Arenas
The following is a list of all known hidden Boss Arenas. See each page for more details.
- Blister Burrow Arena (Troglodyte Queen)
- Conflux Mountain Arena (Brand Squire)
- Voltaic Hatchery Arena (Elite Mantis Shrimp)
- Giants' Village Arena (south) (Ash Giant Highmonk)
- Giants' Village Arena (north) (Elite Ash Giants)
- Ziggurat Passage Arena (Elite Alpha Tuanosaur)
- Electric Lab Arena (Elite Crescent Sharks)
- Levant Arena (Calixa (Ascendant))
- Parched Shipwrecks Arena (Elite Beast Golem)
- Berg Arena (Light Mender and Plague Doctor)
- Burning Tree Arena (Elite Burning Man)
- Cabal of Wind Temple Arena (Immaculate (Ascendant))
- Immaculate's Camp (Immaculate's Bird)
- Isolated Windmill (Elite Sublime Shell)
- Mana Lake (Elite Boozu)
These arenas require finishing the Sirocco quest line to access.
- Tower of Regrets Arena (Grandmother)
- Vault of Stone Arena (Elite Crimson Avatar)
- River of Red Arena (Elite Torcrab)
- New Sirocco Arena (Elite Gargoyles)
- Challenger Greathammer
- Ghost Reaper
- Griigmerk kÄramerk
- Kelvin's Greataxe
- Maelstrom Blade
- Mace of Seasons
- Pain in the Axe
- Thermal Claymore