Wikipedia:Spoiler

It is not acceptable to delete information from an article because you think it spoils the plot. Such concerns must not interfere with neutral point of view, encyclopedic tone, completeness, or any other element of article quality (e.g., the lead section). When including spoilers, editors should make sure that an encyclopedic purpose is being served. Articles on a work of fiction should primarily describe it from a real-world perspective, discussing its reception, impact and significance.

The same reasoning for including spoilers when appropriate in articles on works of fiction applies to other types of "spoilers" as well; for example, the optimal strategy for games such as tic-tac-toe, the workings of magic tricks, the solutions to logic puzzles, the answers to riddles, and live radio and television events broadcast on a delay in certain areas of the world such as the Eurovision Song Contest and the Olympics.

But note that this does not mean such information must be included, either. ; it should contain information appropriate to an encyclopedia article on the subject.

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