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Xenoblade Chronicles X: Definitive Edition

Definian Downfall Walkthrough

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Definian Downfall is a Normal Mission in Xenoblade Chronicles X received from HT665: Erio. Check out a full walkthrough of Definian Downfall, how to unlock it, its bosses and enemies, rewards, and should you suggest mercy or killing Fortun here!

Definian Downfall Mission Overview

Mission Details

Client HT665: Erio
Location Commercial District, Central Melville Street
Areas of Interest Commercial District, Industrial District, Noctilum, Cauldros
Summary Mother Fortun is being misused for evil. Work with Erio to bring down the Definians.

Note: Areas of interest are the place(s) you will visit as you progress Definian Downfall

Mission Objectives

・Talk to Fortun on Central Melville Street in the commercial district.
・Talk to Professor B at his research lab in the industrial district.
・Find a resonating madonater in Noctilum.
・Get an octopus board from the xe-dom of Cauldros.
・Talk to Professor B at his research lab in the industrial district.
・Head to Cauldros's Ganglion Antropolis.
・Defeat ER001: Emeroa in Cauldros's Ganglion Antropolis.
・Defeat HP001: Harriess in Cauldros's Ganglion Antropolis.
・Defeat JD001: Juda in Cauldros's Ganglion Antropolis.
・Pursue ER001: Emeroa in Cauldros's Ganglion Antropolis.
・Defeat the Rexoskell at Cauldros's Ganglion Antropolis.
・Pursue ER001: Emeroa to Cauldros's Emerian Battlegrounds.
・Defeat the Rexoskell at Cauldros's Emerian Battlegrounds.
・Talk to HT665: Erio on Central Melville Street in the commercial district.

If you suggested to kill Fortun to get the password, the objectives that involve Professor B will not be part of Definian Downfall.

Also, killing Fortun leads to the Definian Love while suggesting mercy will lead to the mission called Fortun and Glory instead!

How to Unlock Definian Downfall

Unlock Requirements

How to Unlock
• Clear Consequences
• Clear Good Fortun

The table above contains all the requirements needed to unlock the mission, Definian Downfall.

Definian Downfall Walkthrough

Step-by-Step Walkthrough

# Walkthrough
1
After unlocking Definian Downfall by completing Chapter 11, Professor B's Return, and Good Fortun (including its prerequisites), talk to HT665: Erio in the Commercial District to start the mission!
▶ New Los Angeles (NLA) Map Guide
2
After the intro cutscene, proceed to Fortun's location on Central Melville Street. Your choice during the cutscene with Fortun will affect the remaining objectives of Definian Downfall and also the mission you will unlock after completing it.
▶ Should You Suggest Killing or Mercy?
* If you suggested mercy, you will need to talk to Professor B in the Industrial District.

Then, you need to find a Resonating Madonator in Noctilum and an Octopus Board from the xe-dom in Cauldros.

Finally, return to Professor B and talk to them to progress Definian Downfall.
3
Head to Cauldros' Ganglion Antropolis which will be marked on your map. Use the Follow Ball feature (R + X) if you need to. We recommend avoiding the enemies along the way if you can.
4
After reaching the marked location in-game, a cutscene will trigger. Defeat ER001: Emeroa, HP001: Harriess, and JD001: Juda to progress Definian Downfall.

After the battle, pursue ER001: Emeroa, we recommend using the Follow Ball again to easily complete this objective.
5
After pursuing ER001: Emeroa, defeat the Rexoskell. After the battle, pursue ER001: Emeroa and their location will be marked on the in-game map.
6
Pursuing ER001: Emeroa will then lead to another battle with a Rexoskell. After defeating it, talk to HT665: Erio on Central Melville Street to clear Definian Downfall.

Should You Suggest Mercy or Killing Fortun?

Suggest Mercy to Spare Fortun

Choice Consequence
Suggest Killing ・Unlocks Definian Love
Fortun dies
Suggest Mercy ・Unlocks Fortun and Glory
・Fortun lives

While it will take more time to complete Definian Downfall if you show mercy, Fortun will live, and clearing Fortun and Glory gives a few more EXP and Credits compared to Definian Love.

Missables and Points of No Return

Definian Downfall Bosses, Tyrants, and Enemies

Bosses

Name Qty
Rexoskell
x2

List of Bosses

Definian Downfall Rewards

All Definian Downfall Mission Rewards
480 EXP
43000 Credits

Xenoblade Chronicles X: Definitive Edition Related Guides

Missions

List of All Missions

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List of Mission Types
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Normal Missions Basic Missions
Online Missions Support Missions
Time Attack Missions Global Nemesis Missions

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