Simplify the following text for a Grade 9 native English-speaking person.
Original: The game spawned several sequels , with the franchise earning more than $ 1 billion in sales ; the third installment was the best-selling game in North America in 2007 .
Simplified: The game had several sequels , with the franchise earning more than $ 1 billion in sales ; the third game was the best-selling game in North America in 2007 .