Rhydon X Snorlax

The high attacking IV one. Both moves are good, so the IV is more important.

If you have a good Dragonite with DB, I would use that to beat up on Snorlax instead. Dragonite fills the Snorlax attacking niche better than Rhydon, and if you've got a good one, there's really not much purpose in wasting dust on a Rhydon.

ive 2 mudslap earthquake rhydons, both will kill a snorlax of roughly the same level without any dodging unless the snorlax has eq itself. I like using them. Dragonite is good too though as someone mentioned.

In your case id powerup the first one. ms/se

Because of STAB, Mud Slap does the same amount of damage vs everything that Rock Smash does only to Snorlax...

Rhydon with Rock Smash might be more useful in Gen 2, but for now there's zero reason to power it up over MS

I'd go with MS/SE. Stone Edge is a great charge move that comes out of nowhere. He doesn't make a bad attacker against non-water/grass pokes in general.