PS440

The Final Dimensional Duel X (Japanese: 異次元決戦X Different Dimension Battle X), titled Alternate Dimension Showdown X in the Chuang Yi translation, is the 440th chapter of the Pokémon Adventures manga, and the 24th chapter of the .
It is subtitled A Letter from Oak (Japanese: オーキドの手紙 Okido's Letter) in the VIZ Media translation and Oak's Letter in the Chuang Yi translation.
==Plot==
Powered up by the Pokérus, and , being commanded by Platinum for the first time, defeat Charon's with ease. Charon abandons Slowking, calling it "inept and weak", and steers his vessel to the scene of the legendary fight. To his dismay, he sees that is losing its fight against .
Palmer assembles Cheryl, Mira, Marley, Riley, Dr. Footstep, and the Sinnoh Pokémon Association Chairman onto the platform that the main trio, Cyrus, Paka and Uji are, overlooking the scene of the legendary fights. While Diamond expresses his surprise at seeing Riley again, Mira complains that she could have beaten her opponent. , however, laments at the fighting scene that everyone on her platform now looks at, thinking that the only outcome of such a huge fight is more fear, hatred and sorrow.
Palmer appears to agree, but then Diamond notes that the rivalry between , and transcends that of the relationship between Pokémon and humans. Pearl sees the same case with and 's rivalry.
Uji remarks how even a single mistake can cause terrible situations, and Platinum says that everyone makes mistakes, but the important thing is to recognize that a mistake has been made, and ensure that the mistake is not made again, so that if the current state cannot be restored, at least the situation cannot worsen. and approve of Platinum's words, and Cyrus also feels moved by them. Suddenly, Cyrus catches something in his arms. He sees looking up to him with a smile, and Marley then notices that Shaymin's flowers have bloomed. 
Marley, recalling the contents of the letter that wrote to her, then begins to accept that Cyrus has felt the gratitude in his heart. Suddenly, the legendary clash appears to end as all of its participants, bar Darkrai and Giratina, are put to sleep by the former's . Everyone sees Charon hover over, declaring his evil objective once more. Charon uses his machine to control Giratina's next move, which Pearl anticipates as . At this moment, Shaymin springs into action. It plants a on all of the sleeping Legendary Pokémon to turn their into , waking them up. Dialga, Palkia, Regigigas, and Heatran all charge towards Giratina, causing its Dragon Pulse to aim at Charon's vessel instead, and it is destroyed. 
Charon, while still falling, operates on his machine to grant himself full control over Giratina. Giratina catches Charon and it begins to flee, to everyone's shock. Marley suddenly holds her Gracidea upside down. The Gracidea's pollen falls on Shaymin, causing it to transform. It then flies after Giratina. Pearl says that they should chase as well, and eventually, Diamond gets on Dialga, Pearl on Palkia and Platinum on Cresselia. The trio soon lose sight of Giratina.
Platinum suddenly feels her Cherrim's Great Ball move. She looks at it to see that Cherrim appears to be dancing. Platinum realizes that they are heading back to the outside world, and shows Diamond and Pearl the proof by sending out Cherrim, which, after Platinum's explanation, begins to transform into its Sunshine form. As the trio follow the direction of the sunlight, they eventually spot Charon and Giratina nearing a portal into the real world. Shaymin attempts a on Giratina, which shrugs off the attack, before knocking Shaymin away into Platinum's grasp.
Pearl thinks they will not stop Charon in time, and Charon smirks that he would rather trap everyone in the Distortion World instead. He proceeds to fly Giratina through the portal. On the other side, Cynthia orders a from her . A shower of meteors swiftly fall on Charon and Giratina as soon as they are through the portal.
==Major events==
* puts everyone else to .
* manages to wake everyone up and turns into its Sky Forme to attack .
* Charon attempts to escape, but is attacked by Cynthia upon exiting the Distortion World.
===Debuts===
====Pokémon debuts====
* ()
* ()
==Characters==
===Humans===
* 
* 
* 
* (flashback)
* Cynthia
* Palmer
* Cyrus
* Charon
* Riley
* Mira
* Cheryl
* Marley
* Paka and Uji
===Pokémon===
* (Reg; 's)
* ('s; ; debut)
* ('s)
* ()
* (Palmer's)
* (Charon's)
* (Charon's)
* (Marley's; flashback)
* ()
* ()
* ()
* ()
* ()
* (; )
* 
* (; debut)
* (flashback)
* (flashback; ×2)
==In other languages==
de:Finale in der anderen Dimension X
es:PMS440
fr:Chapitre 440 (Pocket Monsters Special)
it:LGA440
zh:宝可梦特别篇 第440话