Ark: Survival Evolved now has Pokemon in it thanks to a mod by Mystic Academy. But who knows how long it will last since, as per the Steam Workshop page, a DMCA notice of copyright infringement has already been filed against the item.
The mod in question replaces all of the dinosaurs in Survival Evolved with a cast of about 30 different Pokemon, including Alakazam and Rapidash. Other than that, it plays exactly like you would expect, except you hunt adorable little creatures instead of giant lizards. Oh, and you can also ride them!
According to Mystic River, the models and animations for the mod were ripped directly from Pokemon X/Y, only making slight changes where it was necessary in order for the mod to work correctly, so it's not surprising that the mod, titled Pokemon Evolved, already has a DMCA notice attached to it.
At least as of writing, it's unclear who exactly the DMCA is from. While it might seem obvious that it would be the work of Nintendo or the Pokemon Company, Mystic Academy apparently told PC Gamer that they believe the take down request was actually submitted by a rival who was also working on their own Pokemon mod for Survival Evolved. As a result, Mystic Academy put out a call to its supporters and fans to protest the current DMCA attached to the mod's Workshop page.
Meanwhile, you can watch YouTuber everynightxRIOT explore the mod in some detail in a recent video. As he says, there's nowhere else you can currently find megalodons and Gyarados swimming in the same ocean.