
As Armored Core 6: Fires of Rubicon‘s story continues to unfold, the power of Coral becomes more and more apparent as you interact with it more. The first level that puts the power of Coral right in your face outside of the near-death experience found at the end of Chapter 1 is Mission 18: Tunnel Sabotage, which becomes available alongside Mission 16: Attack the Refueling Base and Mission 17: Eliminate V.VII after completing Mission 15: Steal the Survey Data. Going deep underground to perform a routine objective quickly becomes a race to stay alive. This guide will provide a walkthrough of Mission 18: Tunnel Sabotage for Armored Core 6: Fires of Rubicon.
More Armored Core 6: Fires of Rubicon Guides:
Armored Core 6: Fires of Rubicon – Full Achievement and Trophy List | Armored Core 6: Fires of Rubicon – How to Change Weapons, Colors, and More | AC Customization Explained | Armored Core 6: Fires of Rubicon – OS Tuning Explained | All OS Upgrades and Which To Unlock Early | Armored Core 6: Fires of Rubicon – How to Defeat the HC Helicopter Boss Fight | Armored Core 6: Fires of Rubicon – How to Defeat The Strider Boss Fight | Armored Core 6: Fires of Rubicon – How to Defeat The Juggernaut Boss Fight | Armored Core 6: Fires of Rubicon – How to Defeat The Sulla Boss Fight | Armored Core 6: Fires of Rubicon – How to Defeat The Balteus Boss Fight | Armored Core 6: Fires of Rubicon – How to Defeat The Smart Cleaner Boss Fight | Armored Core 6: Fires of Rubicon – How to Defeat The Sea Spider Boss Fight | Armored Core 6: Fires of Rubicon – How to Play Multiplayer
Tunnel Sabotage Walkthrough In Armored Core 6: Fires of Rubicon
This level has only simple grunt enemies with a few PCA LCs thrown. There aren’t any challenges that require you to put together a specific build to aid you here. The only suggestion I would give is to have a lighter build with a high EN Capacity Generator since you will need to quickly boost out of the cave that you are meant to descend into at the end of the mission.
Balam’s subsidiary, Dafeng, has hired you to attack the Engebret Tunnel, a former Watchpoint that the PCA intends to repair. You are tasked with destroying the sensor at the bottom of the cave to draw PCA forces away from their base, acting as a distraction.
Once the mission starts, enter the cave and progress through the first few areas of small rooms and crevices until you reach a large cave system. While your blue objective mark will be telling you to go deeper, look up to see a bridge going across the two walls of the area. Fly up there and then go to the left to find another room.

This room contains several enemies, including a PCA LC sniper standing on the second level of the area. Kill the LC to get a Bronze Combat Log.

Go up to the level that the LC sniper was on to see a giant generator. Sitting in front of the machine is a Part Container. Inside you will find the IA-C01W1 NEBULA Plasma Rifle.

With the Combat Log and Part Container collected, head back to the main cave and progress down to the bottom of the area. Feel free to eliminate any enemies you see along the way since will be paid extra for each one destroyed. Once at the bottom, you will find your target inside of a bubble shield. Pass through the shield and destroy the sensor.

While everything seems calm, destroying the sensor will set off a massive Coral eruption which begins to consume the entire cave. You will need to quickly fly back up the path that you took to get into the cave, dodging geysers of Coral along the way. Continue boosting through the cave until you reach the outside where you started.

Once outside the cave, Mission 18: Tunnel Sabotage will be complete!
MISSION REWARDS:
- 130,000 Credits (COAM)
- Bonus Credit Pay depending on the number of enemies eliminated
- C-Rank Mercenaries unlocked in the Arena
This concludes the guide for Mission 18: Tunnel Sabotage. You can check out Gameranx’s guide for Mission 19: Survey the Uninhabited Floating City. Stay tuned to Gameranx for future news, updates, and guides for Armored Core 6: Fires of Rubicon.