As you play through Detective Pikachu, you will need to find what are known as Clues in order to help Tim and Pikachu solve the Case they are presently working on. Unlike Eyewitness Testimony, clues will have to be found on your own within the area you are presently in. However, sometimes valuable Eyewitness Testimony can point you in the direction of a finding a possible Clue. By finding all the clues and obtaining all the proper testimony of an area, Tim and Pikachu will easily solve the case at hand.