Someone with a long pole that appears to have a spike on the end is pointing it at a red balloon on the other side of the wall from him.
A person with a long object stands on one side of a wall and a balloon floats on the other side.
Someone with a long pole is a paraphrase of person with a long object.
Someone usually refers to a person. A long pole is a long object. Also in both sentences there is a balloon on the other side of a wall.
Someone mean a person, a long pole would be considered an object and a red balloon floating on the other side of the wall from him means that the balloon in not on the same side.