# How to Animate Concept Art with AI and Make a Game Trailer

Turn your key art and character renders into short motion clips, build longer shots with Extend, keep the native sound that ships with each clip, and cut a short trailer from several clips in an external editor, with 16:9 for Steam and 9:16 for socials.

_Andreas Edesberg · 2026-10-23 · Game Development_

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A piece of key art sells a feeling in one frame. A trailer has to sell it in motion: the hero drawing a blade, the banner catching the wind, the city lights flickering on as the title lands. The gap between the two used to be an animation budget. Now you can start from the art you already made and get a few seconds of motion back.

That is the loop this guide covers. Set a character render or an environment painting as a start frame, animate it into a clip, lengthen the shot when you need more, and cut several of those clips together into a short trailer. The clips come out of [Sloyd Video Studio](/ai-video-generator), and when a shot needs a line of narration or a specific effect on top, [Sloyd Audio](/ai-audio-generator) sits in the same account. Video and audio generation are part of Sloyd Plus and Sloyd Pro.

## How to Animate Concept Art with AI (Start and End Frames)

The fastest route to a trailer shot is the art you have already approved. In Video Studio you set an image as the start frame, describe what should move, and get a clip back. No re-modeling, no re-painting, and the character stays on model because the clip grows out of your frame rather than a fresh text prompt.

### Start from the frame you already approved

If you have a strong piece of key art or a clean character render, start there. A start frame keeps the proportions, the palette, and the silhouette you signed off on, which is exactly what a text prompt cannot guarantee. If your art lives as a 3D asset instead, render a still of it first and bring that still in as the start frame, the same way you would with a painting. Teams that already make characters with [text to 3D](/text-to-3d), turn concept sketches into models with [image to 3D](/image-to-3d), or paint references with [text to image](/text-to-image) can feed any of those stills straight into a shot.

### Set an end frame when the shot has to land

For a trailer beat, the last frame matters as much as the first. Set an end frame and the clip will arrive there: the hero mid-pose, the logo revealed, the gate fully open. Use it whenever a shot has to resolve on a specific image, and leave it off when you want the motion to breathe.

### Write the prompt around one action

Animated shots that read well tend to have one subject and one thing happening. Name the movement and the mood, and leave the rest of the frame alone, because every extra instruction competes with your art for the model's attention.

Try: _"The knight slowly raises her sword as embers drift past, cloak shifting in the wind, the rest of the frame still, epic and quiet."_

Video Studio takes a prompt of up to 5,000 characters, so there is room to describe the mood, but a short, concrete action beats a paragraph of adjectives. You can also add references, up to 9 images, 3 videos, and 3 audio clips, to steer the look and the sound, and combine a subject image with a motion video so the subject copies that movement.

## How Long Should a Game Trailer Shot Be?

Each generation runs 5 to 15 seconds. That is the right length for a single trailer beat, where one shot carries one idea before the cut.

When a beat needs more time on screen, **Extend** lengthens an existing clip. Extend continues the shot you already have, so the motion carries on from where it left off rather than restarting. It works on one clip at a time: it makes a single shot longer, it does not join two different shots together. Building a sequence out of several shots is the editing step below, and it happens in your editor rather than inside Video Studio.

A workable rhythm for trailer beats:

- **Generate a strong 5 to 10 second shot first.** Get the motion and the framing right on a short clip before you spend time on length.
- **Extend only the beats that need it.** A title card that has to hold, or an establishing shot the music sits under, is worth lengthening. A quick cut is not.
- **Keep one idea per clip.** If you find yourself asking for two actions in one generation, that is two shots and two cuts.

## Adding Sound to Your Trailer Shots

Clips come back with sound generated alongside the picture, so a shot arrives with ambience and effects instead of silence. For a first pass that is often enough to feel out the edit: the wind on the ridge, the crackle of the embers, the low rumble under the establishing shot are already there.

When a beat needs something specific, generate it on purpose rather than leaving it to chance. [Sloyd Audio](/ai-audio-generator) makes sound effects and loops from 0.5 to 30 seconds, and it reads up to 5,000 characters in a voice from the library for narration and barks. You can cast one of the stock voices or design a new voice from a description; Sloyd does not clone a real person's voice. Each audio clip downloads as a 44.1 kHz MP3, which is the format Sloyd Audio delivers, and that file drops straight into your editor under the cut. If you want a lossless master for the edit, convert the MP3 to WAV in a free editor like Audacity first. For the longer version of the audio workflow, see the guides to [making game sound effects with AI](/blog/how-to-make-game-sound-effects-with-ai) and [AI voice-over for NPCs and narrators](/blog/ai-voice-over-for-npcs-and-narrators). Audio generation is part of Sloyd Plus and Sloyd Pro, and it does not use credits.

## How to Make a Game Trailer from AI Clips

A trailer is a sequence of shots, and that sequence is assembled in a video editor, not inside Sloyd. Extend lengthens a single clip; it does not stitch clips together. So the trailer workflow is: generate each beat as its own clip, download the MP4s, and cut them together in the editor you already use, whether that is DaVinci Resolve, Premiere, CapCut, or anything else.

A short trailer that reads well usually has a handful of beats:

- **The establishing shot.** A wide environment painting with slow motion in it, long enough for the music to breathe. Extend it if the hold needs to be longer.
- **The character reveal.** A character render animating into a pose, ideally landing on an end frame.
- **A beat of action or tension.** One clear movement: a weapon drawn, a door opening, a creature turning.
- **The title card.** A clip that resolves on your logo or key art, set as the end frame.

Cut those together, lay your own generated narration or effects under the picture, and you have a thirty-second trailer out of four or five short clips. Generate each beat at the length it needs, keep the file names tidy so the edit is not a scavenger hunt, and leave the stitching to the editor that is built for it.

## Game Trailer Aspect Ratio: 16:9 for Steam, 9:16 for TikTok and Shorts

Pick the frame before you generate, not after. Cropping a 16:9 shot into a vertical cut reframes your character badly, and re-rendering a clip costs less than fixing a bad crop.

| Placement                        | Aspect ratio | Why                                                   |
| -------------------------------- | ------------ | ----------------------------------------------------- |
| Steam page trailer and header    | 16:9         | The format Steam capsules and trailers expect         |
| YouTube trailer                  | 16:9         | Full-width landscape with no bars                     |
| Reels, Shorts, and TikTok        | 9:16         | Full-screen vertical for socials                      |
| Square social post               | 1:1          | Takes up more of the feed than landscape              |
| Store banner or launch strip     | 21:9         | Cinematic strip that crops cleanly on mobile          |

Video Studio outputs 5 to 15 second MP4 clips at 480p, 768p, or 2K, in 16:9, 9:16, 1:1, 21:9, 4:3, or 3:4. Render your Steam and YouTube cuts at 16:9 and a separate 9:16 cut for socials, rather than cropping one into the other. One note on picking a model: you do not. Sloyd routes each workflow, whether you are animating a still, editing, or extending, so the decision is about the shot rather than the model.

## Game Trailer Mistakes to Avoid

- **Packing too much into one clip.** One subject, one action, one beat. Cut several short clips together in your editor instead of asking for a whole trailer in one generation.
- **Starting from text when you have art.** A start frame keeps your character on model. A fresh text prompt invents a character that merely looks similar.
- **Forgetting the end frame.** If a beat has to land on a pose or a logo, set the end frame so the clip resolves where you need it.
- **Choosing the aspect ratio after generating.** Set 16:9 for the Steam cut and 9:16 for socials up front.
- **Trying to join clips in Sloyd.** Extend lengthens one clip. A sequence of different shots is a job for your editor.

## FAQ

### How do I animate a piece of concept art?

Open Video Studio, set the art as the start frame, describe one action such as a slow turn or a banner catching the wind, choose the aspect ratio, and generate. Each generation runs 5 to 15 seconds, and Extend lengthens that clip if the beat needs to hold longer.

### How long can a single shot be?

Each generation is 5 to 15 seconds. For a longer hold, Extend continues an existing clip. Extend works on one clip at a time, so a full sequence of different shots is cut together in a video editor rather than inside Sloyd.

### Do the clips come with sound?

Yes. Sound is generated along with the picture, so a clip arrives with ambience and effects. When a beat needs a specific line or effect, make it on purpose in Sloyd Audio, which downloads a 44.1 kHz MP3 you can drop into the edit.

### What aspect ratio should a game trailer be?

Render 16:9 for your Steam page and YouTube, and a separate 9:16 cut for Reels, Shorts, and TikTok. Video Studio also offers 1:1, 21:9, 4:3, and 3:4. Pick the frame before you generate rather than cropping afterward.

### Which AI model generates the video?

You do not pick one. Sloyd routes each workflow, so the decision you make is about the shot and the frame rather than the model. For a comparison with tools that do expose a model list, read our [Runway alternatives guide](/blog/top-runway-alternatives-for-ai-video-generation).

### Do I need a paid plan?

Yes. Video and image generation are part of Sloyd Plus and Sloyd Pro. Compare the tiers on the [pricing page](/pricing).

## Turn Your Art into Trailer Shots

A trailer stops being a production once each beat comes straight from the art you already made. Animate your key art and character renders into short clips, extend the beats that need to hold, cut the clips together in your editor, and render a 16:9 for Steam and a 9:16 for socials.

Start a shot in [Sloyd Video Studio](/ai-video-generator), paint the references you need with [text to image](/text-to-image), and build the characters behind them with [text to 3D](/text-to-3d) or [image to 3D](/image-to-3d). See how the whole asset loop fits together on the [game development page](/use-case/game-development), or the [e-commerce page](/use-case/e-commerce) for the storefront version, and compare plans on the [pricing page](/pricing).

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Source: https://www.sloyd.ai/blog/image-to-video-for-game-art-and-trailers