YSK just saying "there is a big surprize / shocking ending" regardless of telling the details or not is already a SPOILER. If you suggest someone a film/tv show/game/book etc. please DON'T DO THAT!
from /r/YouShouldKnow
YSK只說 "有一個大驚喜/震撼的結局"，不管是否告訴細節，都已經是SPOILER了。如果你向別人推薦一部電影/電視劇/遊戲/書籍等，請不要這樣做!