The Battle of Castle Anorak starts in the book on chapter 34 (Page 327) and ends on chapter 35 (Page 335), it is a battle against what claimed to be half of the OASIS population against the Sixers. It was started when Parzival lets himself be captured into being an indentured servant at IOI, then he hacked into their intranet using a system of exploits and back doors to get information on what the Sixers know about the Crystal gate, then he escapes the IOI and sends a message to everyone in the OASIS to help them battle the Sixers which goes extremely well.
However, the reason they haven't attacked the Sixers yet was because they put up an indestructible shield that can be kept up indefinitely if the wizard holding it stays perfectly still and puts both of his hands on the orb, after they all have organized for battle it is revealed that while Parzival was in the IOI system he ordered a supply droid to go up to where a wizard holding the Orb of Osuvox was while holding an antimatter friction-induction bomb, then the droid detonated the bomb incinerating the wizard thereby destroying the shield protecting the Sixers from being attacked by the Gunter army. Shortly before the shield went down a few of the Sixers including Nolan Sorrento put down a some toy robots which became massive robots, which Sorrento's was the largest, being Kiryu, also known as Mechagodzilla.
Once the shield went down the Gunter army quickly took down all the other Sixer robots except Sorrento's. All of the high five fired at Sorrento's robot, however only Art3mis' robot did any real damage to it . After they attacked, it was realized that Mechagodzilla shot out a lightning beam out of its mouth that incinerated anything in its path. When it first launched it, Parzival, Art3mis, Aech, and Shoto all dodge it by jumping out of its path. Then Parzival noticed that it had some sort of cool down for it. They all realized they would have to go by his bot instead of attack it since it seemed to be invulnerable. Parzival offered to distract Sorrento's bot in order to allow the others to get to the gate, Shoto, out of vengeance, went to distract instead saying “This bastard is all mine!”. While the others run towards the gate, Parzival sees that Sorrento manages to destroy the robot and his avatar.
In anger of many things, including but not limited to; Sorrento trying to murder him in real life, killing Daito in real life, and now just killing Shoto's avatar, he pulls out the Beta module; a super powerful artifact that grants the user once a day to become Ultraman, a super powerful and near invulnerable alien, and activates it. Becoming Ultraman, after a brief showdown, Parzival manages to kill Sorrento's avatar very easily. However, he knew that he was going to just take control of another avatar. Parzival then runs into the castle while the other Gunters fight the remaining Sixers, and opens the Crystal gate with Art3mis and Shoto. Which then the Sixers detonate the Cataclyst, killing everyone in the sector, except Parzival since he had found an artifact granting his avatar a second life when he played a perfect game of Pac-man. After a short time he enters the gate.
The battle began after Art3mis deactivated the Orb of Osuvox shield and Parzival shouted a battle cry of "First to the Key!", which is matched by "First to the Egg!" by the Joker's Clan. Art3mis continued her surveillance within the castle, observing one of the Sixers playing Adventure. The Sixer did not fall through the ice as did his predecessors, showing that it was the correct game. After watching him a little further, she left to find Parzival.
On the battlefield, Parzival used his DeLorean to charge through the fight. A Sixer jumped from an IOI Spider Tank into his car and reverted its avatar, revealing herself as Art3mis. She informed him that Adventure was being played, but was being played in the wrong manner and would not produce the Crystal Key.
In response to Aech activating the Iron Giant avatar from her workshop and killing many Sixers, Sorrento retrieved Mechagodzilla from his inventory to fight the Giant. After Helen convinced Toshiro Yoshiaki to finally join the fight, he uses his Gregarious 120 to transform his Daito avatar into an RX-78-2 Gundam. Sorrento's Mechagodzilla is destroyed by the combination of attacks from Aech, Daito and Art3mis, who uses a Dust Brain Madball Bomb to kill Sorrento's avatar within the Mechagodzilla.
Parzival, Art3mis and Sho attempt to cross the bridge, but are stopped when I-R0k detonates the bombs that had been set by IOI prisoners. Sho used his Glaive from Krull to cut off I-R0k's arm, and I-R0k retreated. Determining that her Giant was too damaged to go on, Aech used it as a bridge so that the others could cross, until it fell into the lava. Her final act was to give them a thumbs up, a la the Terminator from Terminator II: Judgment Day.
When they arrived in the room where the Sixer is playing Adventure, Sho prepares to kill him with a crossbow, but is stopped by Parzival who realizes the Sixer was trying to win the game. This is proven correct and the Sixer falls through the ice. Parzival stated, "The only way to get the key is finding the Easter egg itself."
Before he has a chance to do so, Sorrento and I-R0k appear, taking Sho hostage. Sorrento threatens to detonate the Cataclyst unless Parzival joins him, and begins the sequence to activate it. I-R0k became alarmed that Sorrento might not be bluffing, realizing that the ten years he's invested in building up his avatar is in jeopardy. Parzival uses the opportunity to fight Sorrento using the Hadouken and Somersault Kick techniques from Street Fighter. Sorrento reaches the Cataclyst where it had fallen during the fight and finishes the detonation sequence, killing everyone on Planet Doom, including himself.
List of Cameos during the battle in the Film
- Iron Giant from The Iron Giant
- Zitz, Rash and Pimple from Battletoads
- The Ostrich and Knight from Joust
- El Dragón, Ambra, Toby and Attikus from Battleborn
- Cyclops from The 7th Voyage of Sinbad
- Tracer from Overwatch
- Scorpion and Cassie Cage from Mortal Kombat
- Rayne from BloodRayne
- Catwoman, Blue Beetle, Aquaman, Batgirl, Joker, Flash, Nightwing and Deadshot from DC Comics
- Lara Croft from Tomb Raider
- Commander Shepard (Female Version) from Mass Effect
- Chun-Li, Ryu, E. Honda, and Sagat from Street Fighter
- Deadites from Army of Darkness
- Master Chief, Spartans, Elite and Grunt from Halo
- Spawn from Spawn
- He-Man from Masters of the Universe
- Stripe and Gremlins from Gremlins
- RoboCop from RoboCop
- Red Lion from Voltron
- Sonic from Sonic the Hedgegog
- Link from Legend of Zelda
- Chucky from Child's Play
- Jason Voorhees from Friday the 13th
- Freddy Krueger from A Nightmare on Elm Street
- Bubble And Bobble from Bubble Bobble
- The Wolf-Man from The Wolf-Man (1941)
- The RX-78-2 Gundam from Mobile Suit Gundam
- Mechagodzilla from Godzilla Vs. Mechagodzilla
- Ripley's Power Loader from Aliens.
- The PO-024 Field Repair Unit E-Frame from Exosqaud
- Leonardo, Raphael, Donatello and Michelangelo from Teenage Mutant Ninja Turtles (Michael Bay)
- Ruby Rose from RWBY