Armored Core 6 Sea Spider boss guide - Best build, weapons, OS tuning, and more

Armored Core 6 Fires of Rubicon does not shy away from pushing you into some really challenging boss encounters. In fact, right from the get-go, the title establishes itself as a tough yet rewarding experience when it comes to boss fights, with the very first tutorial battle against the AH12 HC Helicopter and other adversaries in Chapter 1.

While the first chapter has some really memorable bosses, very few compare to the sheer spectacle and difficulty of the final boss of chapter 2 - the Sea Spider. This one comes packed with some really powerful weapons, backed by a C-weapon frame, highly resistant to impact damage.

Here's a comprehensive guide on how to easily defeat the Sea Spider in Armored Core 6, including the best build to use, weapons, as well as some combat strategies that'll surely help you.

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Best Build to use against the Sea Spider in Armored Core 6 Fires of Rubicon

The Sea Spider, much like Juggernaut, Balteus, and even the Smart Cleaner, is covered with mostly impenetrable armor, making it really hard to deal direct damage. However, I found the plasma rifles, coupled with the Assault Armor expansion, to be very effective in staggering the Sea Spider.

Here's a build that I used for the Sea Spider boss fight in Armored Core 6 Fires of Rubicon:

• Right-arm unit: Vvc - 760PR
• Left-arm unit: Vvc - 760PR
• Right-back unit: Vvc - 70VPM
• Left-back unit: Vvc - 70VPM
• Head: VP-44S
• Core: VP-40S
• Arms: VP-46S
• Legs: VP-422
• Booster: BST-G2/P04/ ALULA/21E
• FCS: FCS-G2/P05
• Generator: VP-20C
• OST Expansion: Assault Armor

Note that while I used Bipeds in this build, it's best to use Tetrapod or Reverse Joints if you're not well versed with Assault Boosting or Quick Boosting. Both Tetrapod and the Reverse Joint legs allow for unparalleled aerial mobility, something that comes really handy against the Sea Spider.

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Tips to defeat the Sea Spider in Armored Core 6 Fires of Rubicon

Despite being a formidable adversary, the Sea Spider is not undefeatable, especially if you're well-versed in the game's combat basics and are equipped with the right set of weapons to take down the boss. Here are a few tips that should help you easily defeat it in Armored Core 6 Fires of Rubicon:

• Much like any other C-weapon, the battle against the Sea Spider is divided into two phases. in the first one, the Sea Spider mostly stays on the ground and uses its cannons to deal damage, whereas in the second phase, it rises to midair and fires with a barrage of Coral-energy projectiles.
• The first phase is relatively easy, as most of the boss' attacks can be avoided using Quick Boost or even Assault Boost.
• The only attack you need to look out for in the first phase is a lunge attack, which can be tricky to avoid. To dodge it, you need to either Quick Boost away from the boss right when it charges and raise its front legs or boost upward before the attack animation starts.
• If you're using a Reverse Joint or Tetrapod build, you'll find it quite easy to deal damage to the boss while staying airborne since the Sea Spider, much like the Smart Cleaner, cannot track midair targets that well.
• In the second phase, it's best to stick to the ground since going airborne can make it a bit tricky to maintain a hard lock on the boss.
• The most damaging attack you need to look out for in the second phase is the energy wheel attack, which can deal a lot of damage and even one-shot low AP builds.
• To dodge the energy wheel attack, you'll need to Quick Boost away from the boss as fast as you can. I recommend sticking to Quick Boost for this attack, as it gives you a higher degree of control over Assault Boost.
• If you time your attacks right using the plasma rifles, you'll easily stagger the boss and be able to deal direct damage.

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Defeating the Sea Spider is all about knowing the proper time to attack and deal damage. While it by no means is an easy boss, the Sea Spider is roughly on the same scale of difficulty as the AH12 HC Helicopter, Juggernaut, and even the final boss of Armored Core 6's Chapter 1 - Balteus.

As such, if you were able to defeat the previous chapter's final boss, you should be able to defeat the Sea Spider easily, granted you're prepared with a well-optimized build.