Duet Night Abyss Psyche Unlock | The Secret Letter System

The character Psyche in Duet Night Abyss is one of the launch characters and is unlocked using the game’s non-gacha, deterministic system called Secret Letters.

The fastest and easiest way to unlock her is by focusing on the Immersive Theater event and the Covert Commission system.

🦋 Psyche Unlock: The Secret Letter System

You must collect 30 of her unique character fragments, called “Thoughts: Psyche,” to unlock her.

1. Complete Story & Unlock the System

• Progress through the Story: You must first complete the main story prologue (Chapter 1) to unlock core systems like Covert Commissions and the Immersive Theater event.

2. Target Psyche’s Secret Letter

• Secret Letter Clues (Currency):

  • You earn Secret Letter Clues (grey scroll items) from daily and weekly missions. 10 Clues are exchanged for 1 Secret Letter for a specific character.

• Set Psyche as Target:

  • Go to the character acquisition menu and choose Psyche’s track. This ensures your farming rewards are tied to her.

3. Farm the Immersive Theater Event (Fastest Route)

• Immersive Theater Mode:

  • At launch, Psyche is the featured character in the Immersive Theater event mode (a challenging, often roguelike activity).

• Run Stages:

  • Play through the Immersive Theater stages. The reward tracks and drops from this mode are specifically boosted during her feature period (usually 28 days) to give you:
    • Psyche Secret Letters directly.
    • Psyche’s Signature Weapon Secret Letters.

4. Run Covert Commissions (The Direct Grind)

• Go to Combat → Covert Commissions.

• Spend her Secret Letters:

  • Use the Psyche Secret Letter you acquired (from Clues or the Immersive Theater) to start a mission tied to her.

• Choose “Thoughts: Psyche”:

  • After completing the mission, you are offered a choice of three rewards. You must consistently choose the reward that contains Thought: Psyche shards (Gold rewards give 10 shards, Silver gives 2).

Summary for Easy Unlock:

The most efficient strategy is to prioritize clearing the Immersive Theater event milestones and use the rewards from that to fuel your Covert Commissions runs. Since the game has no stamina system, you can farm the missions repeatedly until you collect the necessary 30 Thoughts: Psyche for a guaranteed unlock.