Armored Core 6: How to beat chapter 4 boss CEL 240 in AC6 (2024)

Before chapter four of Armored Core 6, I was not totally convinced that I believed in the concept of “objective evil.” What a sweet summer child I was. Evil is real, and it designing bosses at FromSoftware. I’ve played every Dark Souls, and I’m convinced that CEL 240 takes the cake for being the hardest boss FromSoftware has made.

The best description I can give of how hard you’re going to be walloped during this fight is this—you’re the NPC, CEL 240 is the main character. It’s CEL’s game, you’re just playing in it. Or…is it?

How to beat CEL 240 in AC6

First things first, you’re going to need to make sure your AC is set up properly. There are a few philosophies that you can take to approach this fight, but I think one is the best choice. Namely, a build that is balanced in defense and speed, and HEAVY on attack power. I don’t recommend a tank build because CEL simply hits too hard and too fast. You MUST be fast enough to dodge like your AC is straight out of The Matrix—no amount of AP is going to save you.

In terms of weaponry, I personally recommend dual Gatling guns, a 10 cell Missile Launcher, and the Stun Needle Launcher. But this isn’t the only option but rather the product of a CEL Busting philosophy. You need weapons that can track CEL’s incredibly fast movement to dish out some Impact (the missiles), a semi-truck weapon for when you get an opening (Stun Needle Launcher), and something that can dish out massive damage fast for when you manage to Stagger CEL 240 (the Gatling guns).

Related: The best weapons in AC6

What you don’t want to do is use weapons with slow projectile speeds or really anything that can be dodged consistently. Think of it this way—if a highly skilled player would dodge it, CEL 240 will dodge it.

CEL 240 Phase One: The power of Anime

From the thousands of attacks per second to the dashing around in seemingly a single frame, to wave-like attacks that look suspiciously similar to those of Cloud in Final Fantasy…you’re fighting the main character after they discover the power of friendship.

During this phase, CEL will have two major things that you need to watch out for.

• Drones—CEL 240 will deploy about 20 Laser Drones that will all fire at you. Individual shots aren’t fight-enders, but if you stay still for even a fraction of a second, its game over. Keep on the move at all times, and you can sort of ignore these drones and focus on the hard stuff.

• Moonwaves—I say “Moon” waves because of the Moonlight Sword found earlier in this mission, which seems to be the same attack type CEL 240 uses. This is what will kill you. CEL will launch three wave attacks that travel VERY fast and have a massive danger zone. It’s a weaponized crescent moon.

Related: How to get the Moonlight Sword in AC6

The key to defeating this phase is to wait for CEL 240 to make a “mistake” and then capitalize on it. By mistake I mean to give you even a fraction of a second to stop dodging/running/screaming/sobbing and actually play the game. All of the damage you’re going to be able to deal with will be in chunks. This is not a gimmick boss, but it might as well be given the way you can only attack at certain times.

The best way to find an opening is by waiting for CEL’s Moonwave attack. After the third wave (remember, there are three), CEL will stay still for just the blink of an eye. This is when you can hit him with The Stun Needle Launcher or your powerhouse equivalent. You cannot wait until after the third wave has passed you, or CEL will be weebing out again. Rather you must trust that you’ve dodged it and strike first. For me, immediately dodging in the opposite direction after the second wave did the trick.

At any point during the Moonwave attack, launch your missiles on your other shoulder, this is the time to do it. Make sure, of course, that you’ve got a launcher that doesn’t require you to stop moving to fire, or you’ll be a sitting duck.

During this phase, CEL will also rarely launch a sort of Coral Beam directly at the player. This is easy to dodge as it gives the signature “heads up” beeping before it actually shoots, and it leaves CEL vulnerable for a moment like the Moonwave attack. Just make sure you don’t get hit by it, or you might as well restart the fight.

By combining the missiles and the Stun Launcher, you can Stagger CEL 240. The moment they’re staggered, jump in screaming with the Gatling guns. You can actually do about half of CEL 240’s health per Stagger with these things.

Other than that, just be patient. Don’t waste your ammo/focus taking potshots, it won’t help. Stay defensive, wait for your opening, then strike fast and strike hard. Rinse, wash, repeat.

Related: Hardest Bosses in AC6

CEL 240 Phase Two: Everything, Everywhere, All at Once

You did it! The game went into the signature slow motion and everything! Finally, you can…why FromSoftware, why?

CEL, like all bosses, has a second phase. What is NOT like other bosses is the fact that CEL 240 completely dies and then reanimates. It’s pure cruelty. It’s mind games. Of course, there isn’t a checkpoint here either. You’re starting from scratch.

I’ve named this section “Everything, Everywhere, All at Once” for exactly that reason. You’d almost need a superpower to even keep track of everything CEL is doing. In addition to all the Phase One attacks (which are upgraded with more drones and an X-shaped Moonwave that is significantly harder to evade), you’ve got some new stuff to watch out for.

• Wingblades—CEL will summon about 10 blades and sweep them across the floor in a line. There are two slight variations, one that must be dodged sideways, and one that must be dodged vertically. The warning that it’s coming is CEL moving their arm back and the blades appearing in the air. If the blades start on the side, dodge to the side. If they start above CEL, dodge vertically.

• Angel of Death—CEL will only do this towards the very end, and it is as beautiful as it is lethal. CEL turns into a Coral Jet type of situation and dive-bombs at you again and again from every which way for three total dive-bombs. The warning is that CEL will float into the air for a moment, and a small red Coral jetstream will be left behind for just a moment before the transformation. To dodge these, you must evade left, then right, then up at the PERFECT moment. It’s hard. Really hard.

In this phase, CEL can hurt you before you can hurt CEL. During the reanimation, CEL will be using the drones from Phase One to pepper you. During this time, there will be a couple of lines of dialogue between Walter and Ayre. When Ayre finishes her second line, which ends with the word “environment,” is when you can begin your attack.

Here’s how I recommend doing Phase Two. Be an absolute maniac. Phase One was all about patience, whereas Phase Two feels like a time bomb. CEL simply has too many attacks too quickly, you can only evade for so long. From the moment the second round starts, you want to be directly above, or directly below CEL 240. Go on an aggressive offensive the whole time, and make sure you’ve saved as many Repair Kits as possible.

Being right up on CEL will allow you to deal extra damage, but it is high risk, high reward. You will certainly have more trouble evading attacks with this strategy, so you mostly want to use audio queues. Listen for the telltale beeping, and make sure you’ve got energy left to spam evade when you hear it.

Two good staggers will do the trick for Phase Two, so you just need to beat CEL at their own game—throw out every attack possible all the time and don’t let up for even a second.

It’s…finally over

There is no Phase Three. You did it. You actually did it. The whole key to defeating CEL is to significantly change your playstyle from the First to Second Phase. In Phase One, you must be a tactician, finding the exact right moment to strike. In Phase Two, you must be a rampaging beast whose only goal is filling that sweet sweet Stagger Meter.

When it comes down to it, CEL 240 is actually extremely squishy. All offense, no defense. This is the thing we must exploit.

It’s important to remember, there is a deal of luck involved in every boss fight. I had attempts where I staggered CEL immediately and absolutely melted Phase One, and I had attempts where I couldn’t even touch them. Do your absolute best to stay calm and don’t get frustrated with yourself when you keep losing. The fact that you didn’t get as close this time doesn’t mean you’re somehow getting worse at the fight, it just means you had an unlucky round. Keep a level head and stick to the plan, and you will win. It just might take a while.

When I defeated CEL, it was after losing for hours on end, trying out multiple different builds, and eventually winning with 1AP left. I’m not exaggerating either, I have the proof.

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