Instructions
Travel to Goldenrod City, marked on your in-game map. Enter the building marked "Goldenrod City Game Center."
Sit across from the old man at the gaming table. Press "A" twice to begin a round of "Voltorb Flip." When you begin the game, you will see a 5-by-5 grid with a few extra squares at the end of each row and column. The grid is where you will uncover the squares, and the extra squares tell you additional information.
Read the numbers on the extra squares carefully. The number at the top tells you how many coins that row or column can get you. For example, if the final square at the end of the row says "03" at the top, the number of coins in the first row will only add up to three. The number at the bottom tells you how many voltorbs there are. For example, if it says "2" on the bottom of the final square at the end of the row, that means there are two voltorbs in that row that can end your game. "Voltorb Flip" is about adding up the coins in each row and column to ensure you do not accidentally uncover a voltorb.
Uncover all of the squares in a row or column that say "0" on the bottom. This means there are no voltorbs anywhere in that column or row, so you can safely uncover them all to give you more help in figuring out the locations of other voltorbs.
Calculate how many coins you have earned across each row and column. For example, if you have uncovered two squares in a row that read "1," you have two coins uncovered. If that row claims to have three coins, it means you still have one more coin and two voltorbs hiding in the row.
Uncover shared squares where the amount of voltorbs is low. For example, if you have a row and a column that both have a single voltorb, chances are good that you can uncover the intersecting square without uncovering a voltorb.
Uncover additional squares when you figure out which ones won't have a voltorb under them. When you know certain squares have voltorbs, it gets easier to calculate them in the row or column they share. The game ends when you uncover all of the "x2" and "x3" squares in the grid.