This challenge will be interesting. You must make a chain of 6 Pokemon where the last letter of the Pokemon above that Pokemon is the first letter of the Pokemon's name. The first letter of the first Pokemon must match the last letter of the last Pokemon to complete the chain.
An example of a chain:
Bulbasaur
Rhydon
Nidoking
Geodude
Ekans
Swinub
Just as a note, you can use Nidoran M or Nidorino in order to get Nidoking as an example but you cannot evolve a Pokemon if it will break the chain.