IGN : draconecro
Answer 1: the most playful of the lake trio is Mesprit
Answer 2: The effects caused by encountering the Pokémon can be described as the loss of knowledge, emotions and will. These things can happen by, respectively, looking into Uxie's eyes, touching Mesprit, and hurting Azelf. This can be interpreted as Uxie keeping its eyes closed (to prevent the memory loss), Mesprit fleeing from Trainers (so as to not be touched), and Azelf's ability to enter another being's body (so as to avoid harm).
