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| Pokémon Adventures volume 42
Volume 42: The Battle of the Mystri Stage/Mystri Stage Battle is the 42nd volume of the Pokémon Adventures manga and the second volume in the HeartGold & SoulSilver chapter. It is authored by 日下秀憲 Hidenori Kusaka and illustrated by 山本サトシ Satoshi Yamamoto.
In VIZ Media's translation, this volume is published as volume two of a separately numbered series, "Pokémon Adventures: HeartGold and SoulSilver".
VIZ edition only
The VIZ Media release of this volume also includes the first four rounds from Volume 43. This is because PS460 is the final round of the HeartGold & SoulSilver chapter and VIZ Media was already publishing the Black & White chapter as a separately numbered series. A similar split was done with Volume 14 and Volume 15, where the last round of the Gold, Silver & Crystal chapter was moved from the beginning of Volume 15 to the end of Volume 14.
Pokémon is not the first series to have manga story arcs redistributed this way in VIZ Media's history. For example, two chapters were moved out of Volume 17 of Dragon Ball in order to localize it as the first volume of Dragon Ball Z.