The person you are gaming against may not be some 12-year-old whiz kid. It could be a 90-year-old grandmother. Hamako Mori is known as the "gaming grandma." She has been named the oldest gamer on YouTube by the Guinness Book of World Records. Mori has over 250,000 subscribers on her channel. You can watch her play games like Final Fantasy VII Remake and Borderlands 3. Grand Theft Auto V is her favorite game to play.