Does Castform change type with Sandstorm or Fog?

Question

Also, is it immune to damage caused by Sandstorm?

Comments

I know it doesn't change its look.

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weather ball is still normal type in sandstorm.

Answer 1

No and it is not immune to sandstorm damage.

Answer 2

Castform changes it's look and types only in Hailstorm, Rain and Sunny weather, so it isn't immune to Sandstorm