I thing it is that place in pinwheel forest but it is covered with rocks at the entrance. I have encountered colbian (i ran). How do I make the rocks disappear?
You have to catch/defeat Cobalion. Running from it does nothing. Now, just defeat the E4/Alder again to make Cobalion reappear.
Source: Fighting Cobalion myself
Rumination Field is an area where the Legendary Pokémon Virizion can be captured. It can only be found once the player has caught Cobalion, on the southeast side of Pinwheel Forest.
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