While Fortnite has been capitalizing on marketing crossover events and tie-ins for some time, Call of Duty: Warzone has largely been bereft of them. It's unclear why Call of Duty: Warzone hasn't featured crossover content, but perhaps it was waiting for the right opportunity. That's about to change, however, as Activision has announced a very big marketing crossover. Call of Duty: Warzone will soon start Operation Monarch, a tie-in with the film Godzilla vs. Kong.