This is a walkthrough for Veilstone City Gym in Pokémon Brilliant Diamond and Shining Pearl (BDSP).
Veilstone City Gym is the 3rd gym in the game, although you can delay it and complete the 4th gym before it. The gym itself resembles a fighting dojo with a bunch of sliding walls obstructing your path.
How to Reach the Gym Leader
From the entrance, head all the way left, towards the left-hand side wall. Go up, between the wall and the left-most rooms with the Black Belts inside. When you reach the corner, push the sliding wall right. This will cause the gap in the sliding wall to align with the red stairs nearby.
Go back down and return towards the entrance. Step into the room with the Black Belt directly ahead from the entrance and push the yellow sliding wall below the Black Belt left. Go north past the Black Belt, stopping when you’re between his room and the next. Give the sliding wall on the left a good push.
Head south back towards the entrance again. Now go through the space between the central set of the rooms and the ones on the left. Ahead, there’s a tyre blocking the way. Push the yellow sliding wall near it to the left. Continue north and push the next yellow sliding wall left.
Now head back down, then go left towards the left-hand side wall again. Shove the first yellow sliding wall to the right, to its original position. Ta-da! You should now be able to head all the way north along the left set of rooms. At the end of these rooms, push the sliding wall near the top right.
You’re halfway there. Go south through the newly created gap, along the corridor between the left and center rooms. Stop at the halfway point, where the next tyre is, then squeeze right. Keep going right and shove the nearby sliding wall so it’s misaligned (we’ll fix it later).
Go up, past the nearby tyre. Guess what? Push the next sliding wall to the right. Now head south towards the bottom of the gym. Step inside the Black Belt’s room on the right. It might not seem possible, but nudge the sliding wall below him right.
Exit the room and go along the corridor on the right. After passing through the gap you just made, push the sliding wall between the two right-hand side rooms left, back to its original position. Go down again and re-enter the room you were previously in. Head north through the gap in the sliding wall.
In the next room, again, this can be slightly confusing. There are two sliding walls along the right side. Push the bottom one right. You figured it out yet? Return towards the bottom and go through the right-most corridor again. At the top-right corner, shove the sliding wall left.
Yes, we know this is a little repetitive, but go back towards the bottom, then pass through the two right-hand side rooms once more. After exiting the last room, turn left and shove the final sliding wall left. From here, return towards the entrance, then go all the way through the center-most rooms.
If done correctly, you should come face to face with the Gym Leader!
Black Belt Darren
Black Belt Jeffery
Black Belt Rafael