WaterRock
Water/Rock weaknesses
Water/Rock is weak to Grass, Electric, Fighting and Ground, and takes 4× from Grass.
When Water/Rock Pokémon are hit
4×Hits hardest
2×Super effective
½×Not very effective
¼×Barely scratches it
Its two types separately
Multiply the two to get the result. For example, Grass deals 2× × 2× = 4×.