The investor, who co-founded Chewy.com, has acquired a nearly 10% stake in the Grapevine-based video game retailer.

Ryan Cohen, the entrepreneur who built Chewy.com into a pet-supply giant and sold it for more than $3 billion, is now pitching GameStop Corp. on a lofty goal: becoming a true competitor to Amazon.com Inc., according to a person familiar with the matter.

The Grapevine-based video game retailer’s shares jumped as much as 28% in Tuesday trading after Bloomberg News reported Cohen’s plans late Monday.