yes, the first time you speak to him, you have to complete the pokedes, and upgrade to the national dex. Then he will come and congratulate you in the laboratory. The other time he is in pal park waiting for you. Then he explains how pal park works and leaves. Next, he is at his house in either celestic, or eterna city. He will give you the upgrade (which is needed in order to obtain porygon Z.) and will leave again. If you have an action replay, than you can enter the shaymin event, and then head to the route right outside of the Pokemon league. Then he will be at the very end where the ocean is, with the ancient rock with writing on it. Last, Shaymin will appear, Oak tells you to go and catch it, and when you go back, he will have disappeared.
Chat with our AI personalities
Listen to Professor Oak's Talk show until he says Smoochum are swarming. Go to Lake Acuity capture a Smoochum then evolve it into Jinx.
If you have the National Pokedex, Prof. Oak will be in a house in southern Eterna City.
in the house beside enterna citys gym
You have to go and talk to Professor Oak in Eterna City. He's in the small house that's closest to the building that leads to the cycling road.
either by cheating or a wifi event (but wifi event expired)