you can easily found it in map 4
Chat with our AI personalities
20,000 dollars if you find a big collector
You can find Cobalion in Mistralton Cave and once you do. You might want to save and soft reset every time if it isn't. It is hard to find though.
Pinwheel forest, after catching cobalion in the guidance chamber.
Mistralton cave on route 6.
Leave and return to the cave and Cobalion will have returned. So then you may capture it. I suggest Timer Balls.