MSTing /ˌɛmˌɛsˈtiː.ɪŋ/ or MiSTing /ˈmɪstɪŋ/ is a method of mocking a show in the style of the television series Mystery Science Theater 3000 (MST3K) and, in particular, is a form of fan fiction in which writers mock other works by inserting humorous comments, called "riffs", into the flow of dialogue and events.