An artist known as Varmintz (via Reddit) has designed a curious drawing in which he shows us the beta concept of a series of Pokémon that did not make it to video games.
In the image, specifically, we see 12 Pokémon creatures most disparate. Some of them are nothing more than a different version of the Pokémon that finally appeared in video games and in anime.
The first versions of 12 Pokémon creatures in their beta phase
In the image, from what we can guess, a very different version of Omastar is clearly seen. Maybe it could be an intermediate evolution between Omanyte and Omastar, who knows. The thing is, these Pokémon concepts could really exist, as some images of them were recently leaked.
Beautiful Sugimori Art of Beta Pokemon by Varmintz from r/fakemon