An engine assembly (500) comprises a combustor (510), a fuel cell stack (520) integrated with the combustor (510) wherein the fuel cell stack (520) is configured to direct fuel and air exhaust (522) from the fuel cell stack (520) into the combustor (510), and a pre-burner system (540) fluidly connected to the fuel cell stack (520), wherein the pre-burner system (540) is configured to control a temperature of an air flow (545) directed into the fuel cell stack (520). The combustor (510) is configured to combust the fuel and air exhaust (522) from the fuel cell stack (520) into one or more gaseous combustion products that drive a downstream turbine (112).