Might not be the best of movesets, and I know this is like the fifth Gyro-Curse moveset posted, but here it goes:
Ferrothorn @ Rocky Helmet
Ability: Iron Barbs
EVs: 4 HP / 252 Atk / 252 Def
Relaxed Nature
- Gyro Ball
- Curse
- Bulldoze
- Body Press
Gyro Ball is STAB, and good with Ferrothorn's low speed. Curse is a good setup move and lowers speed to buff Gyro Ball even further. Bulldoze is good coverage for fire, electric, and steel types that resist steel and would make Gyro Ball not as good (Bulldoze lowers speed but you wouldn't be using Gyro Ball on those types anyway). Body Press is more coverage and takes advantage of Ferrothorn's massive defense.
The main flaw with this moveset is Water-Flying types (that's Gyarados, Mantine, Pelipper, Swanna, and Cramorant). I'm not sure how much these mons see play (I mostly play UU, and can't use Ferrothorn), but running into one would be very messy.
If you think that this moveset sucks, tell me.