Ehem, Grass mono champion in Kanto, Johto, and Hoenn. Grass mono on FR/LG was way too taxing.. Damn Charizard. Seriously. It was easier in Johto (Gold) where Meganium can at least learn Earthquake to deal against Fire types, and one of my mons was lucky to have HP Ice to deal against flying and other grass types. Then a normal mono, and the first mono I have ever completed, which was also quite a challenge was an Electric Mono with a FR/LG semi hack (or an incomplete one) FR/LG hack called "Lightning Yellow" that enables a Pikachu (that can evolve into a Raichu) as a starter.
Good god i wish i can find and repost my old Monotype shenanigas back in my FR/LG Grass mono and that Electric Mono where i tasted the hate coming from a Charizard (against my Grass mono) and a Rhydon (against my electric mono) who all came from the same Rival in different runs X-x
The person below me wants to do a Fairy type mono in S&M