Complex sentence: Alfred finally locates the Cloudburst, which is a giant tank personally operated by the Arkham Knight, but it is too late to stop him as the device is launched and all of Gotham City is flooded with fear toxin.
Split into simpler sentences: Alfred finally locates the Cloudburst, which is a giant tank operated by the Arkham Knight. The device is launched and all of Gotham City is flooded with fear toxin.