Using Clip Studio Paint EX, we will explain how to easily create special effect backgrounds using keyframes.

First

First, I created a basic base of 1920 x 1080px, 350 dpi, and set it to seconds + frames, and will give a rough explanation.

[1] Creating the background

(A) Pink (B) Yellow (C) White central pillar, (D) White aurora stretched radially, (E) Dust 1 (F) Dust 2 sprayed, (G) Core cloud pattern, one sheet, prepare using the images as reference. * (D, E, F) Background is pink to make the drawing contents easier to understand.

[2] Layering

Rotate the "(G) Core Image" you created earlier by 90 degrees clockwise to create another one called "(G-2) Core 2 Image". Place them from the top while setting the layer effects. Assemble them in the following order: (D) Aurora/Add (30% glow), (E, F) Dust/Add (Glow), (G) Core 1/Add (Glow)/(G-2) Core 2/Add (Glow), (C, B, A) Background/100% normal, and you'll end up with something like the photo.

[3] Move it with keyframes

Create a new timeline and set it to 13 seconds. The start and end settings are important, so decide them now. In this example, set the start frame to 0 seconds + 1 frame and the end frame to 13 seconds + 12 frames.

The keyframe movements are fixed for the background (ABC). (D) The aurora rotates, and (E and F) the dust expands while rotating. First create keyframes for (G) Core 1. Set the opacity to start at 0% and repeat at 100% every second, completing almost one rotation (359 degrees) in 13 seconds. Once assembled, duplicate it as (G-2) Core 2, and purposely shift (G) Core 1 to follow (G-2) Core 2 so that it starts at the 12th frame of (G).

(E & F) Dust has a slow initial movement, so I accelerate it and then move the frame ahead. (E) Dust (small grains) expand slowly, and (F) Dust (large grains) expands faster to create a sense of depth.

When you look at it in the layer frame, the final trajectory will look like the image.

When it's complete, it will be a 13-second background. I think it will be more effective if you add a character to it.

It's very important to review your work many times during the production process to ensure it matches your image. Have a good life as a creator.