Causes Earth damage to all enemies.Description
Quina learns Earth Shake by eating an Adamantoise, Earth Guardian, and Shell Dragon. The earliest it can be learned is after the party has the Blue Narciss from the Adamantoises around the Qu's Marsh on the southwest island.
Earth Shake damages all grounded enemies with Earth damage by the following formula:
Where Rnd means a random number, while MOD means modulus operation. "Rnd MOD x" can be read as a random number between 0 and x-1.
The bonus part of the calculation is boosted by +50% if Quina is wearing a Twist Headband, Bone Wrist, Gaia Gear, or Germinas Boots. The bonus is halved if Quina is under Mini or the target(s) have Shell.
Earth Shake can do good damage, especially when Quina wears Earth-boosting equipment, but its downside is that it does not work on flying opponents, and all the toughest opponents, including the superbosses and final bosses, fly. Quina could opt to use Twister or Frog Drop against flying opposition. Of the enemies it does work against, few are actually weak to Earth.
Though Earth Shake is Quina's most powerful damaging ability as per spell power, it pales in comparison to what the other party members' best attacks can do. Quina is better of powering their Frog Drop by playing frog catching, which no enemy can resist or avoid unlike with Earth Shake, or setting themselves up for Limit Glove.