According to "The Tale of the Aiwha Pod," a Kaminoan myth, the Ancient Trench refers to a submerged ravine situated on the planet of Kamino; this underwater trench served as the location for a battle that took place between Protas, a monster-god, and the sentient [kikla]. The kikla formed a military force and confronted Protas to dispute his dominion over the oceans of the world. Protas took on their challenge, and after a month long conflict, he emerged victorious against his opponents.
The Legends short story "The Tale of the Aiwha Pod," released in 2005, features the Ancient Trench; Ryan Kaufman authored this story, which was included in the Star Wars: Republic Commando: Prima Official Game Guide.