Earthquake

=Move= Smashes a tail, foot, or fist into the ground, causing an earthquake. It's a powerful Ground-Type attack that inflicts 100 damage and has 100 accuracy, with 10 PP. Earthquake has no effect on Flying Type Pokémon, Levitating Pokémon and Pokémon using Magnet Rise move

Effects

 * Double Damage on a Pokémon that is underground

Move that can make a combo

 * Gravity: All flying, levitating Pokémon can be attacked with ground type moves, in addition it cancels and negates the moves Bounce, Fly, Splash, and Magnet Rise, making Earthquake attack all Pokémon, except the ones using Protect, Detect, Dive, and Shadow Force and the ones that have the ability Wonder Guard
 * You can make a double battle combo with 1 of your partner's Pokémon if they're a type weak to Ground moves. Let them use Protect, Magnet Rise, or anyting protecting them from ground moves and then use Earthquake. It should hit the opponents Pokémon hard, and your partner will stay protected.