Complex sentence: Large retail stores such as Walmart and Target began carrying CCGs and by the end of September, Hasbro was convinced on its profitability and bought Wizards of the Coast for $325 million.
Split into simpler sentences: Large retail stores such as Walmart and Target began carrying CCGs too. By the end of September, Hasbro's interest in the CCG market was made manifest when it bought Wizards of the Coast for $325 million.