Weaving Narrative Threads of a Trailer
Story trailers have a number of tools at their disposal to communicate narrative:
Narration
Title cards
Dialogue
In-game text
Gameplay footage
Press quotes
When these threads are woven together well, they form a cohesive narrative which flows from one story point to the next. When woven together poorly, it feels like a mishmash of disparate thoughts haphazardly put together. Or a thread might get dropped entirely which means resetting the story and starting from the beginning!
Not all story trailers use every single one of these, but will typically have some combination of them. If any one of these elements is in a trailer, it's best of the serve the trailer's story. If each element starts telling their own story, that means more individual threads for the audience to keep track of.
Just imagine trying to watch a film in your native language which had subtitles with a different set of dialogue, and that's only TWO threads to keep track of. The more mismatches between each narrative thread, the more confusing the trailer will be, and the less likely the audience will be to attempt to engage with any of it. Humans are very good at spotting patterns, and if the pattern they see is "This trailer is all over the place" then they're probably going to disengage.
Each of these threads are fully capable of telling a story on their own, but they have their strengths and weaknesses.
Narration can easily sum things up in a way which a mix of dialogue typically cannot (e.g. "In a land of timeless beauty..."), but similarly can be juxtaposed with corresponding visuals to illustrate what the narration is talking about. The downside of narration is if poorly executed it can feel sales-y, generic, or even conflict with the style of the game or its story.
Title cards can also sum things up quickly (e.g. TIME MOVES WHEN YOU MOVE), but when poorly written can sound very generic and undifferentiated (e.g. "In a world not her own, where resolve will be tested, truths will be questioned, and devotions will be doubted."). Also, title cards take up screen time from game footage or fight for its attention.
Dialogue is great because the audience knows it's material straight from the source. This makes it feel more authentic when compared to sales copy written by a marketing team. The downside is it's very difficult to "find the story" using only dialogue, whether due to the trailer editor's level of experience or because there isn't much exposition in the dialogue. Sometimes you'll get lucky and either there's voiceover in the game which perfectly spells out the narrative like a trailer narrator would.
In-game text has a similar benefits to in-game dialogue, but it's much more difficult to use in trailers because people have to read it, which means the rest of the shot can't be too essential to the story since eyes typically gravitate to text; you don't want word bubbles to fight for attention with flashy visuals.
Gameplay footage can tell a story on their own, but some games will do a much better job of this depending on their design. A game like Virginia has great gameplay footage for storytelling because it's designed to work without dialogue. A game like New Super Mario Bros. where the characters don't really change their expressions much will be harder to use to tell a story.
Threads can also be a single storyline being intercut with another one like in this trailer for Hellblade 2: Senua's Saga.
Another way of thinking about narrative threads is all of these story elements are in a relay race where one of them takes a run, hands the baton to the next one who continues racing before handing it off again etc. The worst situation is where one of these threads sets something up, they hand off the baton and the next person decides to go in another direction entirely. This is one reason this trailer for Red Dead Redemption 2 is so confusing; most of the dialogue feels disconnected from the previous line, which makes it feel like a new narrative thread is starting each time.
Here's another example of a trailer with several narrative threads which quickly get very difficult to keep track of:
This trailer has these threads going through it:
Title cards about the story
Title cards about the characters
Title cards about the gameplay
In-game text
Gameplay
Let's assume that the trailer was edited in a way which gives ample time to pay attention to each and every one of these threads. In this trailer they're all doing their individual thing with little to no regard for the other. From the beginning there's a lot of confusion. There's a title card: "The sudden spread of 'Murk' begins to threaten the world" which is followed by dialogue: "There doesn't appear to be anything out of the ordinary with your tree." This dialogue is inconsistent with the idea of darkness spreading.
The one bit where multiple threads do seem to be working together happens next with the title card: "A fierce hatred" which is followed by "A man burning with revenge" and his dialogue "I will destroy everything connected with the divine." These work together to tell the story about this character. Unfortunately most of the rest of the trailer is a complete and utter mess; it's like four different bands playing different songs at the same time.
This trailer gives me headaches just thinking about it.
Another way a thread can be lost is if one is poorly paced. For example, this trailer for Atomicrops has the title cards: "FARM, MARRY, KILL." but the amount of time between "MARRY" and "KILL" is twice as long as the first two. My expectation is for "KILL" to happen roughly at the same time interval, so when it doesn't my brain was preoccupied with whether or not it would continue, and even when it did show up it felt odd.
For a good example of multiple threads working together look at this trailer for 198X:
The voiceover starts with "This is not just a beat 'em up" and says the same about a few other game genres while showing footage from those games. It continues with: "This is the story of my life" and shows what look like story cutscene moments of the protagonist's life. This is followed by a press quote which says "Over-the-top Arcade-action meets coming-of-age drama." The press quote nicely reinforces the idea of a narrative game centered around arcade games. It may feel redundant, but it's adding specificity and authority from a 3rd party.
This all might sound obvious to you when it's pointed out like this, but time and time again I see a lot of game trailers (at all budgets!) which fail to make even the simplest say/see edits. If you're still new to making story trailers I recommend using just one or two of the threads I described, and then adding on more as necessary.
Here's how I think these threads rank in order from most to least difficult to edit with. I'm not including gameplay footage because you can't really make a trailer with no footage at all. These vary a bit based on the game's design, but this has been my experience:
(Most to least difficult)
**** In-game text
*** In-game dialogue
** Trailer title cards
* Trailer narration
This trailer uses in-game dialogue as the audio track, but it doesn't really weave together with the visuals, so it's not terribly cohesive (I still like this trailer)
If you consider the history of movie trailers, this somewhat reflects the order in which the styles of trailers emerged. The first trailers tended to use a lot of expository title cards to describe what is happening (this is also because the first films with sound didn't emerge until the late 1920s). Later, a lot of movie trailers used trailer voiceover by people like Don La Fontaine or Hal Douglas. When that fell out of favor a lot of trailers relied on only dialogue to tell the story. Using footage alone to tell a story can be the most difficult, but again it really depends on the visuals available to edit with. Some games' visuals are just that much easier to use to tell a story.
Not all games specifically need a story trailer, but if the narrative is especially important to the game, you probably want it to be the second or third trailer in your campaign. Hopefully this helps you wrap your head around how to do it!
