Communications Arc

* Anime
* Manga

The **Communications Arc** is the seventh arc of *Dr. Stone* as well as the second arc of the Stone Wars Saga.

Destined for war in the spring, both sides prepare for battle. The Kingdom of Science race to make a cell phone, while the Tsukasa Empire revives an army of people. A gift left by Byakuya becomes a key component in the Kingdom of Science's plan to avoid bloodshed.

## Summary

### Building the Cell Phone

In order to beat the Tsukasa Empire, the Kingdom of Science will make a cell phone. Their first task is making gold wire, but they test the device with cotton candy first so they don't waste materials. Knowing Homura was left behind as a scout, Senku delivers some cotton candy to her as well. The cotton candy is a little grainy, which they fix by switching the method of spinning from back-and-forth pulling to a rotating gear spun at a constant speed. The children and elders of the village begin working on making gold wire while Chrome and Kaseki build a water wheel. This allows them to graduate from man power to renewable energy, and they make batteries to store the power generated. Next, they celebrate Christmas by testing out their brand-new light bulbs.

With not much to do, Chrome goes spelunking with the new batteries and headlamps since he can explore further into the caves. Meanwhile, Kaseki and Senku try making vacuum tubes. Turns out the bamboo filaments aren't strong enough and they lack the necessary material. By chance, Suika brings a rock up the mountain to see the first sunrise of the new year, causing the rock to glow, showing the presence of tungsten. With this, they collect a mining team to collect more of the rock.

While in the caves, Magma attempts to save Senku from falling into a mica pitfall, but they both end up trapped anyways. Chrome saves them with a water siphon while Senku and Magma discuss science. Ultimately, the trio end up better friends by the time they get to the skarn deposit, and Magma rushes them back to the village in time to celebrate Senku's birthday.

Having collected and made all the necessary components, the cell phone can finally be assembled. In the mean time, Senku makes items to improve the quality of life of the villagers. Using one half of the cell phone, Chrome and Ruri share the first phone call in the Stone World to test the device. Ruri reveals one of the 100 Tales, and Senku discovers that his father Byakuya had left a glass record behind for him.

### Preparing for War

They build a record player to listen to it, the record containing a short message from Byakuya and one of Lillian's songs. Gen figures out they can use Lillian's song to persuade members of the Tsukasa Empire to join their side. Chrome overhears their conversation and decides to join them in the deception. The second cell phone is then to be delivered to the Tsukasa Empire by Gen, Magma, and Chrome. Using sound bombs to distract Homura so the cell phone team can escape and then using a flash grenade to stun and almost capture her, they manage to delay her so the phone team has a head start. A team from the village then trail her using powdered scheelite that Senku put onto Homura's hands, then using a pincer attack trick and capture her properly.

The cell phone team arrive at the boundary of the Tsukasa Empire and find Tsukasa's pile of statues. Magma recommends breaking the limbs so they can't be revived, but Gen chickens out. They plant the cell phone under Senku's grave marker, but accidentally alert Ukyo to their position. Taiju and Yuzuriha find the phone and are informed of Senku's plan to trick the other members. Meanwhile, the cell phone trio are trapped and Magma and Chrome sacrifice themselves to let Gen escape back to the village to complete the deception plan.

As a first test subject, Taiju asks their guard Nikki to come to the phone, and after answering several of her questions about Lillian almost-correctly and playing the recorded song, Nikki decides to join the Kingdom of Science. In another part of the Empire, Chrome gets captured by Ukyo while Magma runs back to the village to tell them what happened. They decide to mobilize and head to the Empire. Senku builds a steam engine while Chrome gets interrogated by Tsukasa, Hyoga, and Ukyo. The steam engine is completed and the Kingdom heads to the empire, leaving behind the elders and children in the hopes the Empire can be defeated before they're attacked.

Wanting to upgrade the steam engine into a tank to save Chrome, they create carbon fibre shielding out of plastic and paper. At the same time, Chrome wants to escape so that Senku and the others won't have to save him, and uses random items to free himself from his cage and trick his captor Yo. Having convinced a large portion of the Empire to switch sides, eventually Ukyo overhears the phone call. He keeps up the charade despite having heard through Gen's deception immediately, with the demand that no one dies in the battle. It turns out he'd seen Yuzuriha collecting and remaking the statues Tsukasa had broken, and had hope in the Kingdom.

### The Battle Begins

With the tank completed and Tsukasa and Hyoga out of the way, they decide to rush the Cave of Miracles and retake it in 20 seconds, bloodlessly. Before they can make gunpowder to defeat Tsukasa, the man arrives, bringing Hyoga and the cell phone along and destroying Gen's deception. They fight once more, protecting the scientists inside the cave and hoping for a miracle. Senku creates nitroglycerine, an explosive. They use it to bargain with Tsukasa, and agree to a ceasefire as long as they can find and revive Mirai Shishio, Tsukasa's younger sister.

The Shishio reunion is short-lived, as Homura escapes and blows up the Cave of Miracles, and Hyoga stabs Tsukasa through the lung. The injured Tsukasa and Senku team up to defeat Hyoga. Hyoga is defeated and him and Homura are jailed. Tsukasa lays dying, instructing the Kingdom of where to find all the statues he smashed so they can be saved. Senku tells Tsukasa he'll try to save him using the power of Petrification.

## Story Impact

* Several cell phones are built.
* Senku reunites with Taiju and Yuzuriha.
* The Kingdom of Science defeats the Tsukasa Empire.
* Tsukasa is revealed to have become an MMA fighter to earn money for his comatose sister Mirai.
	+ Due to Senku using the stone formula on her statue, Mirai wakes up perfectly healthy.
* Hyoga betrays Tsukasa for his own goals.
* Tsukasa is fatally wounded.
* The Ishigami Villagers witness depetrification for the first time.

## Characters Introduced

* Nikki Hanada
* Ukyo Saionji
* Minami Hokutozai
* Yo Uei
* Mirai Shishio
* Tetsuya Kinomoto

## Inventions in Order of Acquisition

*For a complete list of inventions in more detail, see Inventions and Discoveries.*

* Cotton Candy
* Water Wheel & Hydroelectric Power Plant
* Lead-acid Batteries
* Vacuum Pump
* Light Bulb
* Tungsten
* Telescope
* Cell Phone
* Record Player
* Flash Grenade
* Steam Engine
* Automobile
* Carbon Fiber
* Nitroglycerine
* Dynamite

## References

1. ↑ Dr. Stone Manga: Chapter 51
2. ↑ Dr. Stone Manga: Chapter 52
3. ↑ Dr. Stone Manga: Chapter 53
4. ↑ Dr. Stone Manga: Chapter 54
5. ↑ Dr. Stone Manga: Chapter 55
6. ↑ Dr. Stone Manga: Chapter 56
7. ↑ Dr. Stone Manga: Chapter 57
8. ↑ Dr. Stone Manga: Chapter 58
9. ↑ Dr. Stone Manga: Chapter 59
10. ↑ Dr. Stone Manga: Chapter 60
11. ↑ Dr. Stone Manga: Chapter 61
12. ↑ Dr. Stone Manga: Chapter 62
13. ↑ Dr. Stone Manga: Chapter 63
14. ↑ Dr. Stone Manga: Chapter 64
15. ↑ Dr. Stone Manga: Chapter 65
16. ↑ Dr. Stone Manga: Chapter 66
17. ↑ Dr. Stone Manga: Chapter 67
18. ↑ Dr. Stone Manga: Chapter 68
19. ↑ Dr. Stone Manga: Chapter 69
20. ↑ Dr. Stone Manga: Chapter 70
21. ↑ Dr. Stone Manga: Chapter 71
22. ↑ Dr. Stone Manga: Chapter 72
23. ↑ Dr. Stone Manga: Chapter 73
24. ↑ Dr. Stone Manga: Chapter 74
25. ↑ Dr. Stone Manga: Chapter 75
26. ↑ Dr. Stone Manga: Chapter 76
27. ↑ Dr. Stone Manga: Chapter 77
28. ↑ Dr. Stone Manga: Chapter 78
29. ↑ Dr. Stone Manga: Chapter 79
30. ↑ Dr. Stone Manga: Chapter 80
31. ↑ Dr. Stone Manga: Chapter 81
32. ↑ Dr. Stone Manga: Chapter 82