1. Metagross
Metagross is the beast of steels and runs the show.
2. Steelix
Steelix was pretty difficult to stop in my playthrough of gold. Steelix has a ridiculously high defense that makes him a good wall.
3. Aggron
Can anyone say tank? this Pokemon is a great choice for a clean up in generation 3
4. Lucario
Lucario was one of those Pokemon that release i couldn't wait for. When i got the Riolu egg i was trying to hatch it right away. Lucario is a great lead off.
5. Empoleon
Empoleon is a good choice for a starter in generation 4. So why didn't he get a higher rank? well his dual type makes him weak to fire, and he doesn't use much steel type moves.