As far as I am aware the Pokemon unknown do not evolve. They are just a Pokemon that has several different shapes. These often look like letters and can be collected to form an alphabet.
Unkown(pokemon)
28
The Pokemon Unkown.
really nothing
You can't but you can trade them
unkown no one knows
All the Unkown are in Celestic Ruins
If you mean Unkown as in the pokemon, you can't.
Nothing happens.
# 114 is the Unkown, they can be found in the Salaceon Ruins in Salaceon Town.
I believe the entire alphabet, including others such as ? and !
in almost every cave earl in the game