Pokémon Diamond and Pearl miss the strange beta designs of their creatures
Arceus, Garchomp or Hippodown had quite a different look and personality in their early days.
Garchomp beta on the left, end on the right. Comparison of Dr Lava on Twitter.
Although Pokémon as we know it is among the most important IPs in the world, there is a whole community dedicated to studying the most primitive of the saga: the discarded designs of their worlds, their logos, the evolutionary lines that Game freak had initially raised for this or that creature, the designs lost in space and time and what we call a "beta Pokémon". Several of the latter have appeared in the 4Chan text tables over the weekend, all pertaining to Pokémon Diamond and Pokémon Pearl.
For the most clueless about it, the term that happens to us refers to provisional designs that were used for many of the creatures we know today, and although in general the final 'sprites' for each Pokémon are usually better than their conceptual versions, beta Pokémon can help us understand the conceptualization behind each design, and also hide interesting secrets that fans love.
In the specific case of the indigenous creatures of the Sinnoh region, fans have found beta versions of the legendary Arceus, Shaymin, Regigigas, Darkrai and Giratina, Togekiss, Yanmega, Vespiquen, Cranidos and Rampardos, all the evolutionary line of Garchomp and Luxray, Hippopotas and Hippowdon, Probopass, Carnivine, Abomasnow, Rotom, Finneon and Lumineon. Most of them look contextually similar to the final version, with nuances. For example, while Regigigas hasn't gone through any major changes, Giratina wasn't much different from Landorus-T in its early iterations. Rampardos and Arceus have also gone through very big changes, for example, and from the original Darkrai there is still the logo of the Japanese movie.
Pokémon Diamond and Pearl are among our favorite generations of the saga, and fans have been several Nintendo Directs eagerly awaiting the announcement of remakes for Nintendo Switch. For now, we will have to settle for various spin-offs such as Pokémon Unite, as well as leaks of Pokémon beta in the code of the games. If you are curious about this topic, I recommend you visit the profile of Dr. Lava, an eminence in the field.