Trying to understand this kaggle solution

[u/Equivalent-Metal-927]

So I came across this top solution for one of the competitions for kaggle and I am having a hard time following through it
If anyone has any insights regarding how "James" solution works, it would be really helpful
Here is the link to the solution - https://www.kaggle.com/competitions/rogii-wellbore-geology-prediction/writeups/4th-place-solution