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The Memory Disk, chapter 20, is the penultimate chapter of volume 6 and the manga series. It involves the chase scene that goes down between Roger and Angel for the memory disk Angel stole. However, by the time Roger realizes the truth about the disk, it’s already too late: the third big is finally restored and activated, as a catastrophic rainstorm and flood takes over Paradigm City whilst the final battle begins.


Angel pulls out a disk in front of her and asks Roger if he knows what it is, to which Roger gasps, recognizing it as probably being Dorothy’s memory disk. Angel dives towards her bike, to which Roger chases after her. Norman contacts Roger on his wristwatch asking why he lost access to the Griffon’s signal, to which Roger explains it melted, shocking the butler. Roger states he’ll explain later as he lunges towards Angel’s bike, narrowly avoiding bullets from the men he took down earlier, who were beginning to recover and stand back up as R.Divide looks on.

Roger manages to grab a hold of the back seat of Angel’s bike and flips onto it, before reaching towards the disk, which Angel kept in her cleavage. Angel grabs the disc and keeps it out of Roger’s reach, teasing him for being so “impetuous”, stating she thought he was supposed to be a “gentleman”. However, amidst the teasing, Angel realizes she no longer has the disk. She pulls over as Roger hops off the bike, and it turns out he was in fact able to steal it from her. As Angel turns around, an explosion can be heard in the distance of the harbor followed by an oncoming rainstorm.

Roger informs Norman that he’s retrieved the memory disk, but Angel simply looks on and starts laughing, stating she never said that memory disk was Dorothy’s in the first place. She comments on how fun this was before driving away. This frustrates Roger, who asks out loud where the real disk is located. We then cut to R.Divide diving underwater, with Roger heading to the harbor whilst being drenched in rain.

R.Divide brings the memory core of Dorothy over to Big Fau as the giant submarine that salvaged the megadeus looks on. When Big Fau awakens, the chair Dorothy is sitting on snaps and she tumbles to the floor. A loud rumble is heard throughout the city, and within a massive tsunami wave emerges Big Fau, now fully restored. “Cast in the name of God, ye not guilty” plays out as Big Fau is ready for action, followed shortly afterwards by Roger calling for Big O, equipped with a new configuration: a 3-headed version of sudden impact on both arms, simply known as the reinforced arms.

The tsunami wave crashes into Big O, followed shortly afterwards by a major flooding of the Paradigm City streets. In the pilot seat of Big Fau, we see Angel, ready to do battle against the incoming Big O. As the 2 bigs begin to wrestle each other, Angel asks Roger if he can hear her, knowing he’s in Big O’s cockpit. She chastises him for his foolishness and states she warned him. Roger doesn’t care, instead deducing that Dorothy’s memory disk is inside the white Megadeus. Angel confirms this, stating it was used for Big Fau’s operating system. Roger is stunned by the name reveal of Big Fau, the third big.

Angel notes that much like with Dorothy-1, R.Dorothy’s memory disk is perfect for this kind of thing, noting the connections between technology prior to 40 years ago. Roger asks Angel if Alex is behind this, only for Angel to reveal that Alex has no idea about this, and only now realizes he’s missing his secretary along with “a lot of valuable data”. As Norman tries contacting Roger, Fouche, Carnot and Robespierre emerge from behind and attack Big O.

Angel asks Roger if he remembers the last time they took a trip to the ocean (Chapter 5), only for Roger to respond he’s not in the mood to reminisce. He then asks her if she’s the “one from across the ocean” that Alex was talking about. Angel replies with the following:

“Who knows? I’m just an ordinary woman”.

The 3 foreign megadeuses then attack, with Robespierre and Fouche lunging towards Big O, only to be skewered by the black megadeus’ hip anchors. Big O then proceeds to use it’s 3 impact arms on Carnot, annihilating it with 1 punch. The impact causes an underwater explosion, causing Dastun to wonder what’s happening down there. Big O then heads in for the kill and is about to land a punch on Big Fau, but Roger stops at the last second, hesitant to do something that may ultimately kill Dorothy.

Angel points out how Roger appears obsessed with the androids' memory as Big Fau fires torpedoes from it’s forehead, blasting Big O back. Norman is on the intercom, and pleads for Roger to return to the surface, citing that not only is Big O unable to take this kind of punishment, but it wasn’t prepped for an underwater fight this time around. Roger doesn’t listen and has Big O use triple impact to launch itself back up towards the ascending Big Fau, whose using it’s wrist cuffs to propel itself through the water.

Angel notes that much to Roger’s chagrin, Big Fau is a water based unit, before then using the wrist cuffs to propel Roger and Big O back down the ocean once again, hurtling Big O into a submerged building. Norman once again begs Roger to return to the surface, stating Big O is too weak with this equipment to beat the white megadeus, only for Roger to respond that Dorothy’s memory is inside that thing and they can’t be allowed to escape, as Big O once again uses triple impact to lunge itself towards it’s opponent.

Norman acknowledges that Dorothy’s memory may be inside Big Fau, but by continuing this fight, Big O might destroy both the white megadeus and Dorothy. Roger exclaims that this may be true, but he must risk it. Angel reports back to the Union on an intercom, stating Big Fau is operational and she’s in control of it, but Big O is in hot pursuit, before Big Fau’s chest opens up and unleashes a series of ocean mines, bombarding Big O with explosions.

When this isn’t enough to stop Roger and Big O, Angel questions why they’re so determined to save Dorothy, only for her to stop for a moment, seemingly realizing the extent of Roger’s attachment to Dorothy. She then bursts out laughing whilst teasing him for risking death to gain Dorothy’s memory disk, saying he’s “one in a million”. Roger and Big O finally catch up to Big Fau, and as Normans past words echo of how Dorothy can still function, but won’t be the same without her memory, Big O uses triple impact to land a direct blow onto Big Fau, as Paradigm City is completely flooded by the rainstorm.

Similarities To The Anime[]

  • Much like in ”Twisted Memories” and ”The Big Fight” of the anime, a chase ensues for Dorothy’s memory which is stolen in order to fully reactivate Big Fau.
  • Paradigm City begins to face some form of catastrophic incident with similarities to the Event as Big Fau and Big O prepare to engage in the final battle of the story, in this case a massive rainstorm that floods a large amount of Paradigm City, which is implied to be how part of the city sank below the harbor 40 years ago.


  • Megadeus: Big O, Big Fau, Carnot, Robespierre, Fouche
  • It’s never explained whose memory disk Angel had for the chase scene in this chapter, with the only 2 other possible candidates being Rosco Fitzgerald and Red Destiny, with both of them being shown to possess the same type of disc drive Dorothy uses.
  • Paradigm Gallery reveals the identity of Big O’s 3-headed version of Sudden Impact is known simply as “Reinforced Arms”, as well as the fact that the reason it was prone to self-destruction was due to them not being built for underwater usage, with the water pressure causing too much stress in conjunction with the extreme levels of force it generated.
  • Paradigm Gallery also reveals that Big Fau was specifically intended for underwater combat, hence it’s ability to effortlessly cruise through underwater, a statement backed up by Angel in this very chapter. This further ties it to the biblical monster of the sea, Leviathan, as well.
  • Paradigm Gallery notes that the reason for why the Carnot, Fouche, and Robespierre only appear briefly in this chapter is due to the limited number of pages available, and the illustrator initially wanted them to appear for much longer so they could show off how powerful they were. This eventually would come to fruition in ”Roger the Wanderer”.
  • Unlike in the anime, where Big Fau is briefly operational despite of not being equipped with Dorothy’s core memory, in the manga Big Fau only activates once given it, and it didn’t require a large cross-shaped apparatus inside the pilot seat to be cooperative with it’s pilot.
  • Unlike Alex, who went through much trouble getting Big Fau to be fully restored, functional, and cooperative with his command, Angel pilots Big Fau with ease and is instantly accepted as it’s domineus. Combined with Big Fau initially rejecting Alex as it’s pilot at first in the anime, as well as accounting for the biblical symbolism of Big Fau as Leviathan and Angel as Lucifer, or “The Dragon”, and it’s likely the role of Big Fau’s pilot actually belongs to Angel instead of Alex.
  • In the manga, Big Fau’s appearance doesn’t match that of the anime, instead being identical to the way it appeared in flashbacks of the event 40 years ago, implying this to be the true form of Big Fau rather than the Paradigm Corporation reconstruction of the white megadeus.
  • This in turn may be part of the reason Big Fau was initially uncooperative with Alex at first, which matches one of the possible implied reasons Big Duo Inferno eventually killed Alan Gabriel, not being in the original state it was in 40 years ago.
  • Big Fau’s name appears to have been mistranslated, instead being referred to as “Big Four”. It’s also possible that Big Four was the working name for what would eventually be known as Big Fau, or this particular version of Big Fau went by the name Big Four.
  • We learn of new attacks Big Fau is capable of that are never revealed in the anime, specifically head-mounted torpedoes and a torso ring of ocean mines, neither of which are given names in Paradigm Gallery. It’s likely we didn’t see these in the anime due to them appearing to only function underwater, considering Big Fau’s nature as an ocean unit.