After Alundra returns from Torla Mountain, Nestus's brother, Burgus, is kidnapped by the Murgg. Fearing for the life of their son, Meade and Rumi beseech Alundra to find him. Septimus suggests that, because Nestus and Bergus are twins, they will share their subconscious, allowing Alundra to enter the dream through Nestus, but exit the dream through Bergus and retrieve him.
The dungeon is at once both simple and complex, consisting of two essentially identical halves. The twins' dreams are, much like themselves, mirror images; much of the dungeon consists of seeing the solution to a puzzle demonstrated in one of the twins' dreams, and then mirroring this solution to solve the counterpart on the other side. Nestus' dream has a colour palette in shades of blue, representing his timid and cautious attitude, while the excitable Burgus has his half in shades of brownish-red.
Although it is likely that Melzas is the one responsible for inducing Bergus's sleep, the dungeon is different to other characters' nightmares. This is because its purpose is to serve as a conduit between the twins, rather than being intended as a threat to their lives, or indeed to Alundra. Accordingly, there are relatively few hazards, and the Murgg encountered are all found in the central rooms of the nightmare, rather than spread throughout. Overall, it is very much focused more on puzzles than combat.
Most of the transitions between the two halves are made via warp pads, but Alundra later encounters sheets of glass on sections directly bridging the two. By solving a puzzle, the glass will shatter, allowing Alundra to progress seamlessly from the dream of one child to the other. The overall aim of the nightmare is to find three switches that merge phantom statues – present in the entrance area of Nestus's side – into their counterparts in Bergus's side.
After the three statues have merged, Alundra may use the exit in Burgus' mind to face the Terror Twins. Destroying these will allow Alundra to exit Burgus's mind, arriving beside the missing child. Freeing themselves from the Murgg's imprisonment, the two return to Inoa Village.
|Alundra – Meia|
|Beaumont – Bergus – Bonaire – Elene – Fein – Giles – Gustav – Jess – Kisha – Kline – Lutas – Meade – Myra|
Nadia – Naomi – Nestus – Phineas – Rumi – Septimus – Sierra – Sybill – Talis – Thyea – Wendell – Yuri – Yustel
|Berue – Cephas – Jaylen – Jeal – Keysmith – King Miming – King Snow – Kōhei – Lars – Lurvy – Lyman|
Melzas – Merrick – Nava – Nirude – Olen – Ronan – Stenia – Uma – Vul – Wilda – Zane – Zazan – Zorgia
|The Klark – Inoa Village – Tarn's Manor – Coal Mine – Lars' Crypt – Despair Desert – Ancient Shrine|
Coastal Cave – Reptile Lair – Magyscar – Sanctuary – Underground Waterway – Nirude's Lair
Fairy Pond – Murgg Woods – Tower of the Great Tree – Torla Mountain – Nava's Keep – Lake Shrine
|Crest – Dreamwalker – Gilded Falcon – Gazeck – Guardians of the Seal|
Life Vessel – Magic Seed – Murgg – Teleport Arch – Zolist
|Enemies – Equipment – Items|