Seoul Object Story - Chapter 44: Object Exhibition (5)

... looking like a wave with concentric circles.

They collided with each other and fell over, or rolled around after getting caught on something.

They intermittently disappeared and reappeared, using ghostification to spread out in all directions.

However, the Golden Reapers seemed unfamiliar with ghostification, rolling around on the floor each time they used it.

They ran with their little feet, then ghostified when they hit an obstacle.

And they reappeared ...