Have you ever tried to catch mesprit or cresselia? and then they teleported? Well, I will tell you how to catch them!first, go to turnback cave and catch a haunter. If it doesn't have mean look or hypnosis,get some heart scales and go to pastoria city and talk to the guy who can teach old moves.now, fly to eterna city. Get on your marking map. Walk so that you stop at
THE VERY BEGINNING OF THAT ROUTE! now, go to eterna city so that it only takes a step. On your marking map, it'll say cresselia or mesprit moved! Keep going back and forth until its where you are. Look near the grassy patches NEAR THE HONEY TREE NOT THE WATER! since haunter should have a speed of 114, it should go first. Use mean look, then try to lower the life to red. Use hypnosis and get lots of nest, timer, and great balls. Have fun catching it, because they are not that hard to catch. Cresselia knows aurora beam, slash, mist, and future sight. I wouldn't know about mesprit, cause I killed it by accident. Hope you get them! (there are more places Cresselia and Mesprit go its like a hundred long pattern)