Implemented in v2.6, the Move Relearner (or Move Tutor) allows you to reteach your pokemon moves learned at lower levels. Even if the pokemon never actually learned the move, any move listed in their Move Set may be relearned for 1,000 pokedollars. Some evolved pokemon may relearn moves that they could not get otherwise (e.g. Charizard can only learn Air Slash via Move Tutor). In pokemon tower defense, it is mostly refered to as relearn.