In the Heart of Darkness is the sixth and final chapter to the Mysteries of the Deep tale. Every stage is deep underwater and require 10 
World energy for Normal and 15 energy for Hard.
Stage 28 is the boss battle against Domiventus.
Increased chance to obtain:
| Untold Tales Navigation | |
|---|---|
| Mysteries of the Deep | The Atlantean Games • Into the Deep • The Temple of the Deep • Lost in the Deep • Memories of the Deep • In the Heart of Darkness |
| Treasures of Flame and Frost | The Long Road to Nidavellir • Flamekissed Fields • In the Hall of the Dwarven King • In the Hall of the Dwarven King • As the Cold Earth Slept Below • Golden Gilded Hearts |
| See also: Map | |