Rock-type Pokémon

Pure Rock-types

Strong against Fire, Flying, Normal and Poison attacks; weak against Fighting, Grass, Ground, Steel and Water attacks

Sudowoodo

Bug/Rock-types

Strong against Normal and Poison attacks; weak against Rock, Steel and Water attacks

Shuckle

Rock/Dark-types

Immune to Psychic attacks; strong against Dark, Fire, Flying, Ghost, Normal and Poison attacks; weak against Bug, Fighting, Grass, Ground, Steel and Water attacks

Tyranitar

Fire/Rock-types

Strong against Bug, Fire, Flying, Ice, Normal and Poison attacks; weak against Fighting, Ground, Rock and Water attacks

Magcargo

Rock/Flying-types

Immune to Ground attacks; strong against Bug, Fire, Flying, Normal and Poison attacks; weak against Electric, Ice, Rock, Steel and Water attacks

Aerodactyl

Rock/Ground-types

Immune to Electric attacks; strong against Fire, Flying, Normal, Poison and Rock attacks; weak against Fighting, Grass, Ground, Ice, Steel and Water attacks

Geodude
Graveler
Golem
Onix
Rhyhorn
Rhydon
Note: Rhyhorn and Rhydon are actually Ground/Rock, not Rock/Ground
(this has no effect on game play; not even GS's type search function cares)
Larvitar
Pupitar

Rock/Water-types

Strong against Fire, Flying, Ice, Normal and Poison attacks; weak against Electric, Fighting, Grass and Ground attacks

Omanyte
Omastar
Kabuto
Kabutops
Corsola