Swampert is nice.
Dig is not.
1. I suggest a bulky nature, one that takes speed. Quiet nature would be best, since most grass moves are special (other than razor leaf and leaf blade)
2. Take away speed, cause roar doesn't need it.
3. Dig is icky, and just begging for an earthquake. So beat em to it. Use EQ.
4. (OPTIONAL) This is begging for a spiking Skarmory. with whirlwind. Paired with swampy, such a skarm could allow EQs, whirlwind, and toxic. insano.
Earthquake can counter electrics, and if you can get drill peck on a skarmory, that takes out grass types.
But that's just my idea. If skarm gets dominated by a thunder/bolt, earthquake finishes off the electric type. (stealth rock and spiks and toxic if you get it in do A LOT of damage.)
Just watch out for Zapdos.
PS this strategy may have some major flaws and is not guaranteed to work.
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yay skitty!
olim est virgo Troiana
quae incensus cogitat grama esse bonus.
incendit per noctam,
et sic excitavit;
invenit veru magnum ano.