Here's a classic "narrative" mechanic embedded right within a fairly solidly "trad" / discrete action resolution mechanical framework system.
From Savage Worlds Adventurer Edition, page 52:
Edge Name: Scavenger
Requirements: Novice tier (can be taken at character creation), must also have the Luck edge.
Description: Once per encounter the hero may find, "suddenly remember," or dig up some much-needed piece of equipment, a handful of ammunition, or some other useful device. The Game Master decides what constitutes an encounter, and has the final word on what can and can't be found.
Pretty clearly a narrative mechanic. The player invoking this Edge in play puts something on their character's inventory sheet that didn't exist a second before. Now of course, in-game this is retrofitted to "Oh of course, the character was just lucky enough and intuitive enough to know that Object X would be needed at just the right moment," but it's pretty clearly a game mechanic being invoked by the player in such a way that can't be handled by a direct character input in the moment it is invoked.
The character in the fiction doesn't get to pull a Bill and Ted's Excellent Adventure and say, "Oh, remember the trash can!" so (s)he can go back in time and put that exact thing in the storage bin for when the party needs it.
Trash Can! Remember a Trash Can!!!!!! (Billy Ted) - YouTube
Yeah, this is pretty minor, but clearly a narrative mechanic. In some games you can similarly ”remember” people, places, terrain features, etc into existence.