Writing prompt

This one is not a fan Fic but a writing prompt that is vague.

A military transport plane crashed on an island with 300 elite soldiers and they learn that there are people on the island who have lived on the island since the begging time. After learning that they have acquired true peace. they slowly approach the islanders and move into the village with them on one condition. They must kill the "monster" that has plagued them.

I like this idea because you can do it from the perspective of the islanders, a veteran soldier, or even a rookie soldier that was never meant to be on the flight.

Anyways I decided I am also going to put writing prompts in here bc just fanfics are getting repetitive.

Thanks