I want to get Ho-oh in my OR game, and I know how, you have to get the Clear Bell, and use it at Sea Mauville, to open a ring portal, but in order to get the Clear Bell, I have to get the Scanner, I know it's in the underwater portion of Sea Mauville, but I couldn't find it anywhere, please help.
This video will help you find it.
The scientist on the deck will tell you he's looking for an item called the Scanner. You can find this item hidden at the very bottom of the ship. You'll need a Pokemon with Dive to reach the basement area the scientist referred to. Dive into the dark water spot at the south side of the interior of the ship, then swim down the stairs to reach the engine room. Investigate the area near the bottom of the right staircase (keep tapping A around the area) until you get a message that says “There is something glimmering faintly in the water... Will you pick it up?” Select Yes to obtain the Scanner.
Good luck on catching ho-oh! Hope I helped!
The Scanner is located on a very specific tile when you dive underwater at Sea Mauville. It's sitting on the ground as you descend the ramp in the underwater control room. But since the item is hidden, you would basically need a visual guide to help.
This tutorial has step-by-step screenshots that guide you exactly to the Scanner's location. This text-based guide with images might be quicker to skim than a video.
I'll also add a screenshot showing the exact Scanner location here, with this screenshot being sourced from the tutorial linked above.
