That's a pretty accurately designed 24" long Onix that dug itself up out of Amphygory Design's 3D printers. According to the creators, it's quite flexible, so unlike other 3D-printed Pokémon figurines, this one can be displayed the way Onix appears in the games or the anime.
Here's a short demonstation:
24" Flexible Onix Model [AmphigoryDesign, YouTube]
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