Ground and Rock types: weaknesses, resistances and Pokémon
Ground and Rock Pokémon take quadruple damage from Water and Grass moves, take double damage from Ice, Fighting, Ground and Steel moves, resist Poison, Normal, Fire, Flying and Rock moves and are immune to Electric moves.
The balance is even: 6 weaknesses and 6 resistances or immunities.
Ground moves are super effective against Fire, Electric, Poison, Rock and Steel and not very effective against Grass and Bug. Rock moves are super effective against Fire, Ice, Flying and Bug and not very effective against Fighting, Ground and Steel.
To beat these Pokémon, your best pick is Water and Grass moves. Avoid Poison, Normal, Fire and Flying moves, which deal little or no damage.
There are 9 Pokémon with this combination, such as Geodude, Graveler, Golem and Onix.