The Battle of Chulak was battle in April 2003 whereupon Earth attacked Chulak to destroy a Chappa'nok'kek factory that Apophis had constructed. In April of 2003, the Prometheus was diverted from its course to Chulak where Apophis had been building Chappa'nok'kek fighters. At the same time, Cmdr. Sharp led several squads of XCOM troops through the gate to assault the facility from the ground and steal whatever was there. In orbit, the Prometheus encountered a lone Ha'tak and engaged it.