YOU SAID:

the distant past, a powerful race called the Forerunners fought an alien parasite known as the Flood

INTO JAPANESE

遠い過去、Forerunnersと呼ばれる強力なレースは洪水として知られているエイリアンの寄生虫と戦った

BACK INTO ENGLISH

Far past, a powerful race called Forerunners fought against alien parasites known as floods

INTO JAPANESE

はるか過去、Forerunnersと呼ばれる強力なレースが洪水として知られているエイリアンの寄生虫と戦った

BACK INTO ENGLISH

Far past, a powerful race called Forerunners fought against alien parasites known as floods