Order of magnitude scale, in millimetres x 10^X, so -1 is sub 1mm across, 0 would be 1mm & 1 is 1 cm, 2 = 10cm, 3= 1m, etc.

Video evidence is required so we can get an idea of how big the thing is, a picture or diagram may be acceptable if it's a trustworthy source

This is for samples from replications only, the sample in the original video doesn't count

Any magnetic effect is fine whether that's the actual Meisner effect, diamagnetism, or any magnetic effect that can be seen on video

So far we have these examples of replication attempts on video;

https://www.zhihu.com/question/613850973/answer/3136586869
https://twitter.com/TranslateMom/status/1686352245984542721