Unown are found: go to solaceon town. Go to the right side and you'll come to some ledges. Jump over the three ledges farthest right. you'll see a cave. go in it and it's filled with unown. This is the only place u can catch them and they're the only Pokemon in the entire cave.
You can find them in solaceon ruins
Solceon ruins.
#114 is unknown. its found in the soleancean ruins
Unknown(sorry about my spelling) Letter A is the rarest Unknown in all games. You are more likely to find a shiny Pokemon then Unknown A but if you are dedicated then go for it but prepare for frustration.
In Diamond it is in the ruins with the Unknown, I am not sure about Platinum though.
the simble pokemon, unknown.
The Unown are in the Solaceon Ruins.
you can catch a lot of unknown Pokemon A-Z
You can find Pidey in a Pokemon Outbreak in Pokemon Diamond
There are 26 but since there are the ! and ? unknown 28 total
To get a Venusaur on Pokemon Diamond you have to get the National Pokedex and look for its area, if it's unknown then I don't know what to do.
right of solaceon town