Despite being a ditto, Ditto (Transformed) is not found on land, but rather in the water. When you have hunting for pokerus on, and you only have Ditto (Transformed) left, it will continuously hunt on land, meaning you will never capture it, since it is a water spawn.
Despite being a ditto, Ditto (Transformed) is not found on land, but rather in the water. When you have hunting for pokerus on, and you only have Ditto (Transformed) left, it will continuously hunt on land, meaning you will never capture it, since it is a water spawn.