Mattel Chief Executive Ynon Kreiz has been tapped to become co-CEO alongside David Ellison of the combined Paramount-Warner Bros. Discovery once the $81 billion deal closes. Kreiz will take part in day-to-day management, strategic planning and integration of the businesses, while Ellison will remain chairman and CEO. Kreiz will also join the board, and the combined company’s businesses will report jointly to both executives. Mattel shares fell 4.24%.