Sub Seed Ferrothorn is fun to use, or just substitute with a hazard move, curse or bulldoze. The hazards Ferrothorn provides might just be too good to give up though. Anything that tries to scald it fails and doesn't break the sub. Its obviously walled by Heatran, etc, but can be an annoyance to something like incoming Terrakion. A lot of rain teams only have 1 or 2 Pokemon who can 1v1 Ferrothorn, so it is really effective against rain, especially if they cant burn it.