Great Thunder grants the user the ability to generate and manipulate lightning. Zaratras employs this magic power to increase his physical speed and imbue the electricity through his weapons.
Raijin no Shukusei「雷神の粛清, Raijin no Shukusei; literally meaning "Purge of the Thunder God"」: Zaratras attacks his opponent with a massive burst of lightning. It's very similar to Gilthunder's Raitei no Shukusei.
Raijinken「雷神剣, Raijinken; literally meaning "Thunder God Sword"」: While engulfed in lightning, Zaratras lunges at his opponent with extreme speed and delivers a devastating strike with his sword.
Raijin no Sendo「雷神の閃動, Raijin no Sendō; literally meaning "Flash Movement of the Thunder God"」: Zaratras uses lightning to enhance his body and allow him to move at lightning fast speed. It's very similar to Gilthunder's Raitei no Sendo.
Zaratras using Raijin no Shukusei
Zaratras using Raijinken
Zaratras using Raijin no Sendo
Raijin no Sendo
This ability is very similar to Gilthunder's ability, Thunderbolt. However, Great Thunder seems to be more powerful.