Links to Wikipedia’s articles on The Storm Trooper Effect and The Inverse Ninja Law have been showing up on various link sites and aggregators. Following these links and clicking around in Wikipedia and elsewhere comes up with a lot of other interesting terms for plot devices, techniques, characters, and tropes. I compiled some of the ones I liked best below.

Much more like this is available under Wikipedia’s Narratology and Stock Characters categories. The TV Tropes Wiki has large and humorous collections of Narrative Devices, Tropes, Meta Concepts, and others.

Anagnorisis: “the discovery of one’s own identity or true character… or of someone else’s identity or true nature…it was the hero’s suddenly becoming aware of a real situation and therefore the realisation of things as they stood.” In other words, the moment when a character’s ignorance or self-delusion suddenly lifts, with Oedipus’ oh crap moment being the canonical example.

Author Surrogate: “a character who expresses the ideas, questions, personality and morality of the author.” See also: Mary Sue

Character Shield: “plot devices … that prevent important characters from dying or being seriously injured at dramatically inconvenient moments.”

Chekov’s Gun: a technique “in which a fictional element (object, character, place, etc.) is introduced early and in which the author expects the reader to invest. That investment must ‘pay off’ later in the story even if the element disappears offstage for a long interval.” From a letter in which Chekov says: “One must not put a loaded rifle on the stage if no one is thinking of firing it.”

Deleted Affair: “a romantic relationship that is regarded to have occurred at some point in the past of two characters, but is never referred to in the present story”.

Eigen Plot: A plot carefully constructed to use all the character-specific skills or abilities of the hero ensemble… For example, if your team plays Elemental Rock Paper Scissors, they’re going to have to face a water trap, a fire trap, an air trap, and an earth trap.”

Finagle’s Law: Stated as: “The perversity of the universe always tends toward a maximum.”, meaning that ”[the] odds of something happening as the plot unfolds depends not on its actual likelihood, but on its potential for disaster… One is generally left with the impression that the universe is controlled by a malevolent (or at least mischievious) deity who is obsessed with making your life as difficult and humiliating as possible. ”

Flashing Arrow: “an audiovisual cue used in movies to bring some object or situation that will be referred later…The device is not introduced into the plot or the dialogue, but is something peripheral; however made obvious (hence the name) by a particular camera shot or background music.”

Fridge Logic: Plot inconsistencies which are ignored by the characters and not perceived by the audience until after the story is finished, when they suddenly become obvious.

Hammerspace: “a fan-envisioned, extradimensional, instantly accessible storage area in fiction. The concept is jokingly used to explain how characters in animation, comics and games are capable of producing objects out of thin air.” When a cartoon character pulls out a wooden mallet (seemingly from nowhere) and proceeds to clobber another character, that mallet is said to have emerged from Hammerspace.

The Inverse Ninja Law: an observation of martial arts movies and anime which states that “the effectiveness of a group of ninja is inversely proportional to the number of ninja in the group. While a single enemy ninja is often portrayed as a significant threat to the protagonists, a large group of ninja is significantly less of a threat, and as such is easily defeated.”

The Kobayashi Maru: A technique in which a character is brought right to the edge of death, or some horrible outcome, but is spared by the revelation that, unbeknownst to the audience, the preceding events were part of a dream, or simulation.

MacGuffin: ”...a plot device that motivates the characters and advances the story, but has little other relevance to the story. The element that distinguishes a MacGuffin from other types of plot devices is that it is not important what object the MacGuffin specifically is… Its importance will generally be accepted completely by the story’s characters, with minimal explanation. From the audience’s perspective, the MacGuffin is not the point of the story.”

Mary Sue: A character who appears in the story as an absurdly idealized stand-in for the author. “Characters most commonly labeled “Mary Sues” are often characterized by their unusual and dramatic traits and experiences, their similarity to their author or their author’s ideal person and especially their extreme superiority in comparison to other characters.”

The Minnesota Fats: A stock character who happens to be better than the main character at exactly the thing at which the main character excels.

Peripeteia: “a reversal of circumstances, or turning point… A character who becomes rich and famous from poverty and obscurity has undergone peripeteia, even if his character remains the same.”

Plot Coupon: “an object whose possession or use is necessary in order to resolve the conflict upon which the plot hangs, when this necessity clearly springs from the arbitrary decision of the author to make it so necessary. (The name is derived from a joke: when the characters have collected enough plot coupons, they can trade them in for the denouement.)... Structurally, plot coupons can be viewed as the component parts of a divided and dispersed MacGuffin.” See also: Plot Voucher

Plot Dump: Long exposition, usually at the beginning of a work, “by which critical elements of the plot, often involving the back-story, are not depicted directly but are instead elaborated in dialogue by one of the characters or by a narrator.” For example, the scrolling text at the beginning of Star Wars. A (sometimes) necessary evil, considered lazy by some.

Plot Voucher: “one of those useful items that is presented to the hero at the start of his adventure with a purpose totally unspecified, that turns out at an arbitrary point later in the story to be exactly what’s needed to get him out of a sticky and otherwise unresolvable situation.” See also: Plot Coupon

The Rashomon Effect: “The Rashomon effect is the effect of the subjectivity of perception on recollection, by which observers of an event are able to produce substantially different but equally plausible accounts of it. It is named for Akira Kurosawa’s film Rashomon, in which a crime witnessed by four individuals is described in four mutually contradictory ways.”

Red Herring: “a plot device intended to distract the reader from a more important event in the plot, usually a twist ending… The phrase may have originated from the practice of saving a hunted fox by dragging a red herring across its trail to cause the pursuing hounds to lose the true scent and follow the false trail of herring odour instead.” See also

Stormtrooper Effect: a recurring phenomenon in fiction “where minor characters… are unrealistically ineffective in combat against more important characters.” See also Character Shield

Unexposed Contents: A device in which ”[a] container is shown by the author/director, but the contents are intentionally never revealed. Alternatively, an important door may be shown but never opened.” Differs from a MacGuffin or a Red Herring in that “the contents may be important to the characters, the plot and possibly the audience, despite the fact that the viewer never finds out.”

Wedge-type character: “minor background characters that survive an entire saga or series without being killed (i.e. having character shields). However, they tend to suffer notoriously from little to no character development.”