Bonus dungeon (エクストラダンジョン, Ekusutora Danjon?, lit. Extra Dungeon), also known as secret dungeon or optional dungeon, is an optional location that is usually much more difficult than the main game with enemies that are much higher level than on other parts of the game. These dungeons are considered sidequests and often contain the most powerful equipment and, sometimes, summons that can only be obtained by completing the dungeon. The boss fought at the end of a bonus dungeon is often a superboss.
A game can have multiple bonus dungeons. Bonus dungeons are common features added to remakes of older games, to give experienced players new material to test their skills against, and to make the remake more lucrative purchase for people who have already completed an earlier version of the game.
Soul of Chaos Edit
As the original Final Fantasy is the most remade game in the series, it has had plenty of new content added over the years.
Soul of Chaos is the collective name of the four bonus dungeons originating in the Dawn of Souls version that reappear in the 20th Anniversary Edition and iOS versions. The Android version doesn't have any bonus dungeon.
Each dungeon is tied to one of the four worldly elements and are initially sealed by a statue of their element's respective Chaos Fiend. Each dungeon, with the exception of Earthgift Shrine, is significantly longer than any in the main game. Major bosses from future games in the series are fought in the shrines, and the dungeons include many new and powerful pieces of equipment, as well as enemies that were not in the original game.
Labyrinth of Time Edit
The Labyrinth of Time is the new bonus dungeon in the Final Fantasy 20th Anniversary and iOS versions of the original Final Fantasy. It consists of various floors, each one containing puzzles that must be solved on time for the player to proceed. At the deepest floor players will face Chronodia, Master of Time, the new superboss.
Soul of Rebirth Edit
The Soul of Rebirth is a bonus quest in the Dawn of Souls, 20th Anniversary, and iOS versions of Final Fantasy II. It becomes available after completing the game, after which the player can select "Soul of Rebirth" from the menu. Soul of Rebirth gives the player a party consisting of three party members they had in the past, with the addition of Scott, who join with whatever spells, equipment and stats they had when they left the party. Each of the characters' ultimate weapons can be found in the dungeon, and at the end of the quest, the player faces the light half of the Emperor.
Sunken Cave Edit
Located underwater the small island to the extreme southeast of the Surface World, the party will need to dive with the Nautilus. The Sunken Cave has a wealth of chests containing lots of equipment and a few items.
Saronia Catacombs Edit
This optional area is accessible from underwater in the southeast part of Saronia. The party can fight Odin here obtain the Summon spell Catastro, and steal the Gungnir from him, as well pick up some equipment and items from chests.
Lake Dohr Edit
Lake Dohr is to the west of Castle Argus over a small mountain range, requiring the Invincible to reach. The party can fight Leviathan here to obtain the summon spell Leviath. The treasure chests here contain a wealth of attack items, as well as some equipment.
Bahamut's Lair Edit
The cave itself is located to the southeast of Vikings' Cove, but the player must cross the mountains to the east of Bahamut's Lair on the Invincible to reach the entrance. The party can fight Bahamut here to obtain him as a summon.
Eureka contains some of the best equipment in the game. A gateway to it can be found at the bottom floor of the Crystal Tower, but the Eureka Key is required. Doga and Unei unlock the Eureka Key, and give it to the Warriors of Light, granting them access to Eureka, knowing they need better equipment to fight Xande.
??? is an unnamed, secret underwater dungeon present in the 3D remakes. To unlock the dungeon, the player must finish the Mognet sidequest and retrieve every single letter. Located in the cave is Red Dragon, Green Dragon and Yellow Dragon, which have Onion equipment as their common and rare drops, and a secret superboss, the Iron Giant.
Lair of the Father Edit
Lair of the Father is an optional dungeon in all versions of Final Fantasy IV, where the player can acquire the Eidolon Bahamut. The player can visit the cave as soon as they acquire the Lunar Whale and fly to the Red Moon.
Cave of Trials Edit
The Cave of Trials is a bonus dungeon appearing in the Advance and Complete Collection releases. The dungeon has eight floors and the final floor contains five weapons guarded by bosses, one for each of the five party members players can swap out. The weapon can only be acquired if the correct member to wield it is in the party. Each of these weapons correspond to the characters who become available after the Giant of Babil to put them on-par with the rest of the group, who can acquire their ultimate weapons in the Lunar Subterrane. However, still stronger weapons can be acquired in the Lunar Ruins.
Lunar Ruins Edit
Lunar Ruins is a bonus dungeon in Final Fantasy IV Advance and Complete Collection, unlocked by completing the game. The floors are randomized with ten sets of floors of which the sequence of the sets of floor is fixed. In each set, there are five normal floors and a a sixth gate floor, which contains a save point and a door to each playable character's challenge, except for the tenth set, which leads to Zeromus EG, a new superboss.
The mobile phone version of Final Fantasy IV has an all new "EX Dungeon", which is a remake of the Lunar Ruins.
Challenge Dungeon Edit
Every character with their own tale has a Challenge Dungeon. They become available to explore by talking to Challengingway after the tale has been cleared. The Challenge Dungeons are difficult multi-floor dungeons with powerful enemies and often bosses, but for completing them the player receives a rare item or equipment piece. Challenge Dungeons must be completed multiple times to win all the items they offer.
These dungeons are not available in the 3D versions.
Gil Cave Edit
Gil Cave exists only in the second world connecting the Kingdom of Bal to the mainland entrance of the Big Bridge. By following a hidden path in the south of the cave, one can find the Gil Turtle Path. It houses a great treasure of gil, as well as dangerous and extremely powerful Gil Turtles, which are usually encountered every third step. The path may be completed multiple times for more gil.
Phoenix Tower Edit
The Phoenix Tower is a thirty floor tower found in the merged world. There are two doors in every floor: one will unfold the stairwell to the next floor, while the other is guarded by a random monster. Every five floors there will be pots on the right and left sides and one will contain an amount of GP equal to the floor number multiplied by 1000, and the other is revealed to be a Magic Pot.
All other encounters apart from the Magic Pots are inescapable and the enemies tend to hit the party with strong status ailments. Completing the tower awards the Phoenix summon.
Sealed Temple Edit
The Sealed Temple is a secret dungeon in Final Fantasy V Advance. It is located underwater, south of Phantom Village, and contains four crystal shards with the jobs of Cannoneer, Gladiator, Oracle, and Necromancer, although the last lies at the end of the Cloister of the Dead. In the temple the players can find the strongest enemies and bosses of the game, including Omega Mk.II and Neo Shinryu.
In the World of Ruin visiting any areas after obtaining the airship is optional, but doing the areas lets the player recruit new and old party members and obtain espers. Many players consider the recruiting of all playable cast before the final battle as canon, and therefore most areas in the World of Ruin are not really considered sidequests or bonus dungeons.
Cultists' Tower Edit
The Cultists' Tower was built and is inhabited by the Cult of Kefka, a group that worships Kefka Palazzo. The tower is the tallest structure in the game with dozens of floors over four screens of staircases. All offensive commands, except Magic, are sealed, and unless Umaro is brought along, the party is limited to the use of spells and items in battle. At the top lies the unique relic Soul of Thamasa, but taking it causes leader of the cult, the Magic Master, to attack the player.
Ebot's Rock Edit
Ebot's Rock is located north of the town of Thamasa in the World of Ruin. Hidon, a beast that was hunted by Strago and Gungho in their youth, lives there. The cave is dark, and the player only has a small circular area of sight. The player must travel throughout Ebot's Rock, collecting enough Coral from treasure chests that a talking treasure chest will move allowing access to Hidon's chamber. The player can learn Strago's most powerful Lore from it.
Dragons' Den Edit
The Dragons' Den is a bonus dungeon in Final Fantasy VI Advance and subsequent ports located north of the Dragon's Neck Coliseum on an island with a single tree. Access is given once the player has defeated the eight legendary dragons. The player can obtain the most powerful equipment pieces in the game in the den, guarded by the most powerful bosses.
Ancient Forest Edit
Ancient Forest is located in the Cosmo Area accessed with a green, black or gold chocobo, or by defeating Ultimate Weapon first. In the forest the player must solve some puzzles to find rare Materia and weapons.
The sunken Gelnika is a crashed airplane that lies on the Bottom of the Sea to the south of Costa del Sol. The plane can be accessed after the player has acquired the submarine. Even after sinking to the ocean floor, the plane's interior keeps from flooding, allowing for one to enter the sunken aircraft from the ocean. Gelnika holds some of the game's most difficult random encounters, and also some of its best treasures.
Tomb of the Unknown King Edit
The Tomb of the Unknown King is a location near Deling City, and by doing the sidequest inside the player can obtain the Guardian Force Brothers. Most of the areas are tunnels, making the tomb appear straightforward, but if the player backtracks, the viewpoint will change, potentially confusing the player. The player will immediately drop a SeeD rank if s/he decides to venture out of the tomb before his/her objective is fulfilled.
Centra Ruins Edit
The Centra Ruins is on the Centra continent. Upon entering the ruins, a timer begins and the party must find a series of red gemstones and place them in the eyes of statues to acquire the secret code to access the room where Odin is fought. The Tonberry King also appears randomly once 20 or more Tonberries have been killed. Defeating him earns the player Tonberry as a Guardian Force.
Deep Sea Research Center Edit
The Deep Sea Research Center is a hidden island far out in the middle of the ocean, in the very southwest corner of the world map. It is an abandoned, half-sunken laboratory formerly used to research draw effects. In the first area the player must face Bahamut, and after defeating him and earning him as a Guardian Force, the player can advance deeper into the ruins after leaving and returning.
Cavern of the Stolen Fayth Edit
The Cavern of the Stolen Fayth is located in a gorge to the north of the Calm Lands, near the entrance to Mt. Gagazet. The cave hides a fayth that legend says was stolen long ago to prevent summoners from completing their pilgrimage. At the end of the cavern, the players fight a boss, and get the chance to recruit Yojimbo as an aeon for Yuna. In the International and HD Remaster versions, the party can fight Dark Yojimbo after obtaining the aeon, leaving and reentering the dungeon.
Omega Ruins Edit
The Omega Ruins is a large dungeon located within a small group of islands to the east of Spira's main continent. Unlike many of the other locations in the game, the cave must be mapped by the player. At the end of the cave, two deadly bosses await the party: Ultima and Omega Weapons.
Because of the game's non-linear nature many areas and missions are optional. Completing most of the areas is still needed for 100% story completion, although some areas are truly optional, and do not affect story completion.
Ruins Depths Edit
The Ruin Depths is an optional dungeon in the Calm Lands, situated behind and on a lower level than the Calm Lands Ruins. Unlike most areas in Final Fantasy X-2, the Ruin Depths does not have a mini-map, and contains some rare and unique treasures. The dungeon must be unlocked to enter in a complicated process of chocobo raising and exploration.
The boss of the area is the Anything Eater. Once it is defeated, all five sets of locked doors are unlocked; once they are manually opened, the final door giving access to the Amazing Chocobo is unlocked. A Garment Grid with the constant ability of Break HP Limit is the prize for getting to the Amazing Chocobo. The Ruins are not part of 100% completion or the main quest.
Fiend Colony Edit
The Fiend Colony is an optional dungeon located on the Mi'ihen Highroad. The player must dispatch a level four or five chocobo to the highroad from Clasko's Chocobo Ranch during Chapter 5 to access it. To travel through the dungeon, the player will need to destroy stone walls with bombs. Once the player reaches the back of the cave, they will fight the King VERMIN!. Defeating him gets the party a new Garment Grid. Completing Fiend Colony is not needed for 100% story completion.
Den of Woe Edit
Den of Woe is a hidden cave in the Mushroom Rock Ravine accessed if ten Crimson Spheres are collected. Many of the spheres have special requirements to be obtained and are well hidden. The Den of Woe contains no treasure, but has some boss battles. Although Den of Woe is a sidequest, unlocking and entering the Den is necessary for 100% completion.
Via Infinito Edit
Via Infinito is a 100-floor dungeon beneath Bevelle. In the final cloister the party can challenge the game's superboss, Trema. For each cloister block of 20 floors, there are about 6 level designs which appear at random as each one is completed. The dungeon is swarming with monsters, and equipping a Charm Bangle for No Encounters will have no effect. Every oversoulable fiend, except for the Georapella and Precepts Guard, can be found here. Valuable spheres and accessories can be obtained from the defeated bosses. Completing Via Infinito adds to story completion.
Necrohol of Nabudis Edit
The Necrohol of Nabudis was once the capital of the Kingdom of Nabradia, but its remains have become corrupted by the thick Mist that covers the region. The location is not part of the main storyline, and houses the game's ultimate weapon, the Zodiac Spear. The player can access the area as soon as the Dawn Shard has been acquired, which means that the game's ultimate weapon can be acquired fairly early. The Esper Chaos resides in the Necrohol, as do some marks and rare game. However, the party cannot obtain Chaos until they have at least reached Archades, as one of the items needed to reach him requires a miniquest to be completed there.
Great Crystal Edit
Even though Great Crystal is visited as part of the storyline, only a small part of it is mandatory. If the player returns after having obtained the Treaty-Blade, they can travel into the deepest parts of the crystal. The area has no in-game map, and the interior is like a maze with many dead ends and paths that need to be unlocked. The Esper Ultima and the superboss Omega Mark XII reside within the crystal, as well as several rare game.
Henne Mines Edit
Henne Mines is a mandatory story location, but its true depths can only be explored after obtaining ten Espers and asking the geomancer in Jahara to open the locked gate within the mines. At the mines the player will encounter some of the toughest regular monsters in the game, and at the end of the mines, battles the ultimate Esper, Zodiark.
Midlight's Deep Edit
Midlight's Deep is a secret dungeon in the US and PAL versions that features the hardest challenges in the game and is located in the Keep of Forgotten Time. It consists of ten levels and the dungeon can be left at any time, though the party must start back at the first level when reentering. On the tenth and final floor resides the superboss Yiazmat.
The Faultwarrens is an optional location on Gran Pulse. It is where the fal'Cie Titan resides breeding increasingly powerful monsters and pitting them against the party. Some of the tougher missions are fought here, for a variety of prizes.
The Ultimate Lair is located in the Dead Dunes and can be accessed on the "extra day" via a new Cactuar statue that appears outside the Ruins East Gate. The Lair is full of Last Ones, and is imperative to visit to complete a certain side quest, as it is the only location during a regular playthrough where Meonekton Ω will spawn due to having to kill a prohibitively high number (65,535) of the regular monster otherwise. If Lightning already drove a particular species into extinction, those specimens do not appear.
Within the Ultimate Lair, the game clock doesn't stop, even during battle, and Chronostasis is disabled. Lightning must keep moving to reach the deepest level. After defeating the enemies on each level she gains access to warp devices that lead to lower floors. On the last floor she can battle the game's superboss, Ereshkigal.
Most dungeons are not part of the main storyline and are unlocked via sidequests. Thus far all Hard modes of dungeons aren't mandatory, including those based on dungeons that were part of the main storyline.
List of bonus dungeons: | width="33%" align="left" valign="top" | A Realm Reborn
- Sunken Temple of Qarn
- Cutter's Cry
- Dzemael Darkhold
- Aurum Vale
- The Wanderer's Palace
- Amdapor Keep
- Pharos Sirius
- Copperbell Mines (Hard)
- Haukke Manor (Hard)
- Lost City of Amdapor
- Halatali (Hard)
- Brayflox's Longstop (Hard)
| width="33%" align="left" valign="top" | A Realm Reborn (continued)
- Hullbreaker Isle
- Tam-Tara Deepcroft (Hard)
- Stone Vigil (Hard)
- Sastasha (Hard)
- Sunken Temple of Qarn (Hard)
- The Wanderer's Palace (Hard)
- Amdapor Keep (Hard)
- Labyrinth of the Ancients
- Syrcus Tower
- The World of Darkness
- Binding Coil of Bahamut
- Second Coil of Bahamut
- Final Coil of Bahamut
| width="33%" align="left" valign="top" | Heavensward
- Dusk Vigil
- Fractal Continuum
- Saint Mocianne's Arboretum
- Pharos Sirius (Hard)
- Lost City of Amdapor (Hard)
- Void Ark
- Alexander: Gordias
- Alexander: Midas
Midlight's Deep Edit
Midlight's Deep is located on an island east of the Port City of Warjilis. It consists of ten levels of caves, and is home to the most difficult enemies and the best treasure through the Treasure Hunter ability. From the start, only one of the ten levels can be accessed. To get deeper, the player must fight a battle, all of which function like random battles.
Simply defeating every enemy on the screen will not work, instead, the player must find a passageway to the next level that is always hidden in one of five different squares on each floor. To find the exit, a unit needs to step on that square. The tenth level holds a regular storyline battle with the secret Lucavi demon Elidibus, who uses the Zodiac summon which can only be learned from him.
Brightmoon Tor Edit
Some of the strongest enemies in the game reside in these dungeons. At the top of each Brightmoon Tor location is a watch that have enemies at level 90 and above. Although the items the dungeons contain may only be obtained once, multiple attempts can be made to retrieve them. If one failed to notice them the first time, or simply did not have the required equipment, one can try again.
Tower of Agito can be entered via the airship, Setzer, and boasts a hefty challenge. The player must complete five series of battles in which they must defeat 100 of a specific enemy, all of whom are at Level 128. Players may access relic terminals prior to entering each challenge, as they will be unable to leave the area until all 100 enemies are defeated. Rare accessories are available, with the final prize at the top being the game's best accessory, the Agito Insignia.
There is one bonus dungeon in the game, Nasty Dungeon, and it lives up to its name. The monsters comes in a large variety of groups, and the dungeon branching pathways with no real indication as to which path is the correct one. Enemy groups can easily reach up to fifteen, more or less monsters per battle, and surprise attacks can become quite a constant threat inside this dungeon. But the treasure found inside is well worth the player's effort. Unlike many bonus dungeons, the Nasty Dungeon is not strictly optional: the player must enter it to collect the Pegasus just past the entrance. A fairy posted by the chest will warn the player about the danger, advising them to take the MAGI and leave.
There are quite a number of optional dungeon to explore, and they are found in various areas. But some of them becomes inaccessible after a certain point. The dungeons are fairly simple to navigate and contains valuable treasures.
List of optional dungeons:
Holy Tree Tower, Moonsand Ruins, Mysterious Lighthouse and Trial Tower become available after the player obtains the Master Key. Each tower is 100 floors tall with special floors every 10 floors where the player can leave the tower to save. Sometimes the special floors have bosses or a merchant or a treasure chest. Some of the best equipment can only be obtained as random treasures in the bonus dungeons.
In Bravely Default, Dimension's Hasp is an optional dungeon located at the Kustra Archipelago, and becomes available after speaking to either Lord DeRosso in the "Finale" or Sage Yulyana in "The End", although the Sage will also unlock the seal to access the 10th and final floor. Each floor reuses a map from a previous dungeon, and is home to all the game's enemies, as well as equipment that includes the strongest weapons of each type. At the end of the final floor is a secret boss battle against the Adventurer and the Comrade.
In Bravely Second, after Dimension's Hasp is destroyed by Ba'al Diamante, Yulyana conjured three new optional dungeons in the Ruins of Centro Keep in Caldisla, Mount Fragmentum in the Yulyana Region, and the Underflow under Eisenberg. Like the previous game, the dungeons are home to the game's enemies and hold the strongest weapons which are protected by dragons. At the end of Dimension's Caludron is a secret boss battle against the Adventurer and the Comrade.