Seafloor cavern (Legendary #17)

The news spoke of a airtight cave under the sea. Hoping to find some seafloor pokemon, you decide to investigate. The next day, you and your pokemon dive to the cavern, and surface in the airpocket. you remove your scuba-suit, and investigate the area. Other than a large, empty basin on the small spit of land you're standing on, there is nothing here. or so it seems. Taking a second look at the water you notice a statue of a pokemon under the waves.

(you must have the Blue Orb if you want to Awaken Kyogre)