I have a card that hasn't been uploaded because it's unstable. I think my card has the same mechanism as yours. but I think yours is better and more stable. are there many balls inside?
@Labyrenight In fact, one ball is enough for this structure. This structure was first discovered by @935. I just "modified" his structure. The reason for the two balls at the bottom is because of the way this diagram is implemented. Also, I don't usually post pictures of bare structures, so people who are interested will take them apart.
