What does sandstorm do?

All Rock-type Pokémon will now have their Special Defense raised by 50% for the duration of the sandstorm. Also, if a Smooth Rock is held when Sandstorm is used, its duration is lengthened from 5 to 8 turns. read more

Effect Generation II. When this move is used, a sandstorm will brew. This effect will last for 5 turns. This clears any other weather, but will fail when the weather is sandstorm. read more

Sandstorm creates a sandstorm on the battlefield that lasts for 5 turns and induces these additional effects: All Pokemon except Rock, Ground and Steel types and those with the Sand Veil, Sand Rush or Sand Force abilities, lose 1 ⁄ 16 of their max HP at the end of each turn. Pokemon with the Sand Veil ability increase their evasion by 20%. read more