>>57076425It allows you to see actual ghosts (gastly, haunter, cubone, marowak). The only trainers in gen 1 who use ghosts are the channelers in the towers and Agatha. The channelers are not training the ghosts, they are possessed and you defeating the ghosts frees them. Agatha can see and train the ghosts presumably because she specializes in ghosts, so has probably unlocked some latent ability to see them.
