Pokémon was recently hit with what is now arguably the biggest leak in the series' history. True to its name, the Teraleak contained more than a terabyte of previously unreleased information, all data coming directly from Game Freak itself. Of course, a leak of this size left no stone unturned when it came to Pokémon series as a whole.
However, that doesn't mean that every game in the series got “equal treatment.” For example, there was almost nothing to share Pokemon Red, Blue and Yellow losses. Likewise, major unreleased Gen 2 content had already leaked previously. Despite coming much later than the previous two sections of the series, Pokemon Diamond, Pearl and Platinum they appear to have met a similar fate. While the small amount of cut content may be disappointing, it hides far more interesting revelations.
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The Pokemon Diamond, Pearl, and Platinum leaks have one glaring omission
So far, the Teraleak's main attraction has been the Pokemon themselves. Whether it's beta designs of existing Pokemon or never-before-seen unreleased Pokemon, there have been numerous leaked Pokemon designs at the forefront of this conversation. These can currently be viewed in the full Teraleak archive published by Centro Leaks,
Unfortunately for Generation IV fans, Pokemon Diamond, Pearl and Platinum they are largely absent from this section. This is currently a bit of a mystery, compared to Pokemon Gold, Silver and Crystal leak, where the games have simply already been mined for all their value. Likewise, the Pokémon it appears the series have become more widely documented over time, meaning Gen 4 could be expected to keep up with its peers. Luckily, one important aspect of the fourth generation was still ripe to leak out.
The losses of Pokemon Diamond, Pearl, and Platinum have one clear saving grace
What Generation IV lacks in unused Pokemon, it more than makes up for with unique design documents. Diamond and Pearl marked something of a transition period for the series, where the characters became more fleshed out and the world-building became equally ambitious. Both of these traits have been fully realized in the recent leaks regarding the Gen 4.
Similar to Pokémon Black and White leaks, Generation 4 design documents include character biographies. These were clearly never meant to see the light of day, and therefore should not be considered canon in any way. However, they provide interesting insights into the thought process the developers had when creating several major characters.
Likewise, they have become the topic of much fan discussion in their own right. For example, Cyrus is the fourth generation leader of Team Galactic, and his bio suggests that he may be destined to fall on the autism spectrum. The nature of the translation has generated some conflicting accounts, but there is nothing wrong with the headcanons that have emerged regardless.
Pokemon Generation 4 leaks hide a deep knowledge of the series
Furthermore, the fourth generation Teraleak section actually hides some of its depths Pokémon tradition. The world building of Pokémon has been relatively light-hearted in the past, preferring a fairy tale approach instead of any kind of deep dive. This leak has finally cracked open the shell and seemingly uncovered Game Freak's intended vision for the creation myth Pokémon world.
Legendary and Mythical Pokemon have always had an ambiguous relationship, but a diagram in the Teraleak seems to suggest that they exist as two halves of a shared pantheon. This paints Legendary Pokemon as literal gods and Mythical Pokemon as lesser divine beings with a direct familial relationship to their Legendary counterparts. Pokemon designs have always straddled the line between wild beasts and mythical creatures, and these secret documents make that intention clearer than ever.
At first glance, it might seem that there is less leaked content about the Sinnoh region than the others. However, this couldn't be further from the truth. The Teraleak has revealed information that provides much more clarity to both the characters and the story Pokemon Diamond, Pearl and Platinum. Some of the deeper lore is a complete surprise, but it's certainly welcome.