This is the 14667th most frequent German word.
mystischen
"Relating to the mystical or mysterious."
In this sentence, 'mystischen' is the accusative singular adjective form modifying the feminine noun 'Insel' (island), denoting something mysterious or otherworldly.
Das Buch erzählt eine spannende Geschichte über eine mystischen Insel.
The book tells an exciting story about a mystical island.
Here, 'mystischen' is the plural adjective form in the accusative modifying the plural noun 'Riten' (rites), referring to spiritual or enigmatic practices.
Der Film porträtiert eine alte Kultur mit vielen mystischen Riten.
The movie portrays an ancient culture with many mystical rites.
In this case, 'mystischen' serves as the accusative singular adjective form for the masculine noun 'Ursprung' (origin), describing an element related to mystery or esotericism.