Rain Dance is a Water type non-damage dealing move.
When Rain Dance is used, rainfall will be summoned for 5 turns. It clears any other active weather conditions and replaces it. If it's already raining, this move will fail.
While Rain Dance is in effect, due to rain, the base damage of Water-type moves will be increased by 50%, whereas the base damage of Solar Beam and Fire-type moves will be decreased by 50%.