Grass

Ground Attacks

Ice

Ground attacks are most effective against Fire, Electric, Rock and Poison Pokémon. However...

...since all Ground attacks (including Fissure) are totally ineffective against Flying Pokémon, don't expect to hurt a Charizard, Zapdos or Aerodactyl with Earthquake.

Ground attacks are weakest against Grass and Bug Pokémon. (Try something else on Parasect!) Note that a good number of Grass and Bug Pokémon are also half-Poison, thus negating this penalty. Bug Pokémon that are half-Flying (ie, Butterfree and Scyther), however, are completely safe from Ground attacks.

On the other hand, Ground attacks are an extremely effective way of dealing with Ghost Pokémon. Not only because they are half-Poison, but also because the Gastly series have much lower Defense scores than Special scores and Ground attacks are Physical.

Ground attacks are, in general, very strong and those who can learn them typically have high Attack scores, thus making them quite formidable in battle. Ground attacks are everything Rock attacks should be, but aren't.

If you have a Rock/Ground Pokémon, Ground attacks are almost certainly a better choice for your Pokémon than Rock attacks, except for the case of dealing with Flying Pokémon. A strong Normal attack, such as Slash or Body Slam also can take advantage of a high Attack score and would be more reliable and, in some cases, more damaging than Rock Slide. (Rock Slide, however, is handy for special cases, such as Charizard and Moltres).

Fissure is a one-hit KO attack and therefore unlike all other Ground attacks (except in its inability to affect Flying Pokémon). You should learn all you can about one-hit KOs before deciding if Fissure is right your Pokémon (eg, if your Pokémon isn't fast enough, it might not be worth it to you at all).

Bonemerang is more accurate and much more powerful than Bone Club. Bone Club does have twice as many PP, and a small chance of causing the victim to not attack on the turn of its use, but this doesn't make up for its lack of power.

Earthquake sets the standard for Ground attacks. While Bonemerang is equally powerful (and a lot cooler), it's not as accurate as Earthquake. Earthquake is the better choice, but if you don't have an extra TM for it or you just want your Marowak to have a cool attack, you'll still be in fine shape.

Note that while Bonemerang has exactly half the power of Earthquake, it always hits twice (when it does hit).

Earthquake and Dig have equivalent power, PP and accuracy. The difference is that Dig works similar to Fly, in that on the first turn of its use, the attacker burrows underground and out of range of nearly all attacks (Swift is the famous exception). The next turn, the attacker will pop up out of the ground and attack normally, just as if it had used Earthquake.

(By the way, Dig gets the same Average Damage rating as Earthquake because your Pokémon is practically invulnerable for one turn. This, of course, doesn't take Swift into consideration, but it's difficult to numerically represent that. But keep that in mind when making your decision.)

This can be a good method of prolonging battles while a victim is poisoned or burned, or of draining PP, if that is the plan. The big drawback is that it gives advance warning of your attack. If your opponent has a Flying Pokémon, he can switch to it and be assured that it'll receive no damage from the Dig.

Another thing to consider is that Dig is useful in game play to immediately escape from caves and some buildings directly to the most recently vistied Pokémon Center. If you're still playing the RPG side of the game, this extremely useful feature might make you favor Dig over the more straightforward Earthquake.

At any rate, both attacks are quite good and you probably won't go wrong with either of them, if you use them wisely.

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