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The Lost Numbers — Xenoblade Chronicles 3 Walkthrough
Xenoblade Chronicles 3

The Lost Numbers — Xenoblade Chronicles 3 Walkthrough

Guide yourself through Xenoblade Chronicles 3's 'The Lost Numbers' Hero Quest to recruit Isurd and deepen your understanding of Aionios conflict.

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Guide yourself through Xenoblade Chronicles 3's 'The Lost Numbers' Hero Quest to recruit Isurd and deepen your understanding of Aionios conflict.

The "Lost Numbers" quest is a pivotal Hero Quest in Xenoblade Chronicles 3, leading to the recruitment of the enigmatic Hero, Isurd. This quest not only expands your party's combat capabilities but also delves deep into the philosophical underpinnings of Aionios, exploring the lives of those who have managed to escape the endless cycle of war. It’s a multi-stage endeavor that requires careful exploration, strategic combat, and keen observation.

Quest Overview: Recruiting Isurd

Hero Recruited: Isurd

Class Unlocked: Strategos (Healer)

Recommended Level: 25+

Step-by-Step Walkthrough

Phase 1: Whispers of the Lost
  1. Initiate the Quest: After liberating Colony 9 and progressing further in the main story, return to the Aetia Region, Central Aetia. You'll find a quest marker (a question mark icon) near the Gura Flur Cave entrance, specifically around the Alfgar the Wise landmark. Approach the area to trigger a cutscene and overhear a conversation about "Lost Numbers" and a hidden settlement.
  2. Gather Information (Colony 9): Head back to Colony 9. Speak with various NPCs marked with a speech bubble icon.
    • NPC 1: A soldier near the Colony 9 Canteen. They will mention strange readings in the Aetia Region.
    • NPC 2: A supply runner near the main gate. They'll talk about unusual activity around the Gura Flur Cave.
    • NPC 3: A researcher in the Colony 9 Command Center. They will provide a vague hint about a "hidden path" or "unmarked trail."

    These conversations will update your quest log and point you back towards the Gura Flur Cave area.

Phase 2: The Hidden Path
  1. Investigate Gura Flur Cave: Travel to the Gura Flur Cave landmark in the Aetia Region. Instead of entering the main cave, look for a hidden path.
    • Location: From the Gura Flur Cave entrance, head west along the cliff face. You'll need to use your Wall Climb field skill (unlocked via a previous Hero Quest) to scale a small, moss-covered rock face. If you haven't unlocked Wall Climb, you'll need to progress further in the story or complete the relevant Hero Quest first.
    • Environmental Puzzle: The path isn't immediately obvious. Look for subtle cracks or ledges that glow faintly when you approach. Once you climb, follow the narrow ledge.
  2. Discover the Secret Entrance: Following the hidden path will lead you to a concealed entrance, distinct from the main Gura Flur Cave. Enter this new area.
Phase 3: Through the Unmarked Tunnels
  1. Navigate the Tunnels: The tunnels are linear but contain a few minor detours. Be prepared for encounters with standard Aetia Region enemies (e.g., Volffs, Arduns).
    • Key Objective: Your primary goal is to reach the end of these tunnels. There are no complex puzzles here, but keep an eye out for resource nodes.
    • Territorial Monster Encounter: Approximately halfway through the tunnels, you will encounter "Graveclaw Groff" (Level 28 Unique Monster).
      • Strategy: Graveclaw Groff is a large, aggressive Ardun-type creature. It primarily uses physical attacks and can inflict Topple. Focus on breaking its armor with Break/Topple/Launch combos. Its weakness is Ether damage. Consider bringing an attacker with strong Ether Arts (e.g., Mio as a Zephyr, or Eunie as a Medic Gunner with Ether-based Gems).
      • Recommended Party: Noah (Swordfighter), Mio (Zephyr), Lanz (Heavy Guard), Sena (Ogre), Eunie (Medic Gunner), Taion (Tactician).
      • Reward for Defeating Graveclaw Groff: 1000 EXP, 500 G, 1x Nopon Coin (Silver), 1x Ardun Horn (Rare Material).
  2. Reach the Lost Numbers' Hideout: After defeating Graveclaw Groff and continuing through the tunnels, you will emerge into a surprisingly lush, hidden cavern. This is the secret settlement of the Lost Numbers.
Phase 4: Meeting Isurd
  1. Confrontation and Explanation: Upon entering the hideout, you will be confronted by the leader of the Lost Numbers, Isurd. A lengthy cutscene will play, explaining their philosophy of escaping the cycle of war and their efforts to live peacefully.
  2. Isurd's Dilemma: Isurd will reveal that their settlement is facing a threat – a group of aggressive creatures or a supply shortage. He will ask for your assistance.
  3. Assist Isurd: Your next objective will be to clear out a group of "Rogue Ferises" (Level 26-27) that are encroaching on their water supply.
    • Location: Just outside the hidden settlement, in a small, connected cave system.
    • Strategy: Rogue Ferises are fast and can inflict Bleed. Focus on crowd control and taking them down one by one. Use defensive Arts to mitigate Bleed damage.
    • Reward: 800 EXP, 300 G.
  4. Recruit Isurd: After successfully defending the settlement, Isurd will be impressed by your party's strength and conviction. He will agree to join your cause, offering his strategic mind and healing capabilities.

Isurd: The Strategos

Upon recruiting Isurd, you unlock the Strategos class for your party members. This is a powerful Healer class that excels at applying debuffs to enemies while simultaneously healing allies and boosting their Arts recharge rate.

Strategos Class Overview:
  • Role: Healer
  • Weapon: Ether Rifle
  • Key Abilities:
    • Ether Blast: Deals Ether damage to an enemy.
    • Field of Healing: Creates a healing field that restores HP over time.
    • Tactical Insight: Boosts Arts recharge rate for allies within range.
    • Mind Blast: Inflicts Confusion on enemies.
    • Skill: Strategic Mind - Increases debuff duration on enemies.
  • Recommended Characters for Strategos: Taion, Eunie, Mio. Characters with high Ether stat benefit most from this class.

Rewards for Completing "The Lost Numbers"

Reward Type Details
Hero Recruited Isurd
Class Unlocked Strategos (Healer)
Experience Points 2500 EXP (Quest Completion)
Gold 1200 G (Quest Completion)
Nopon Coins 1x Nopon Coin (Silver)
Items
  • 1x Ether Cylinder (Large)
  • 1x Strategos's Manual (Used to level up Strategos class)

Common Pitfalls & Tips

  • Wall Climb Skill: Ensure you have unlocked the Wall Climb field skill. Without it, you cannot access the hidden path to the Lost Numbers' hideout. This skill is typically unlocked by recruiting Juniper (Hero Quest: "Going Beyond Power").
  • Over-leveling: While the quest is recommended for Level 25+, don't hesitate to grind a bit if you're struggling with Graveclaw Groff or the Rogue Ferises.
  • Exploration: The Aetia Region is vast. Take your time to explore and uncover all landmarks, as this will make fast travel easier.
  • Party Composition: For the boss fights, ensure you have a balanced party with at least one Defender, one Healer, and a mix of Attackers. Isurd himself is a powerful Healer, so once recruited, he can significantly boost your party's survivability.
  • Dialogue: Pay attention to the dialogue with the Lost Numbers. It offers valuable insights into the lore of Aionios and the philosophical conflicts of the world.

Completing "The Lost Numbers" is a crucial step in expanding your roster of Heroes and unlocking a versatile healing class. Isurd's strategic prowess will prove invaluable in later, more challenging encounters.

The Lost Numbers - Xenoblade Chronicles 3 screenshot
The Lost Numbers

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