What is the hardest Pokemon to encounter?

Other than Legendary Pokemon and Pokemon that can only be found through evolution/breeding which Pokemon is the most secluded and has the least chance of encountering throughout all 6 generations of Pokemon?

Pleaselog inorregisterto add a comment.

Cryogonal

Cryogonal had a 1% encounter rate in twist mountain in BW

Tynamo was 2nd at 2% encounter rate in chargestone cave

I know this is an old question. But I know something that is Super hard to encounter. These are the conditions for being the hardest wild Pokemon to encounter.

If a wild Pokemon meet those conditions stated above, then it will be the Hardest Pokemon to encounter. I’m not talking about breeding and Legendaries. Pokerus only exist from Gen 3 onwards. And shinies only exist from Gen 2 onwards. I’m not sure for the encounter rate. I don’t think anyone on Earth encounter a wild Pokemon the meet the conditions I stated above. If there is, comment below. Someone tell me if I missed out anything.

Source : Knowlege and Experience

Source, method for finding Shiny Manaphy and the calculations to find Mirage Island