Hi, Nelson. In the Discovered Checks lesson, in the third Advanced puzzle/example (at 11:10 in the video), I think you missed an interesting variation. Instead of capturing our Q, White can avoid the discovered check by moving 2.Kg1 or 2.Kg2. If 2.Kg1, then the Knight fork on f3 works again, and we win the Q. If, on the other hand, White plays 2.Kg2, we have Mate in 2! We can play 2…Qh3+, forcing the White K to g1, and now our Knight fork is checkmate! Did I get this right?

Wow — this puzzle/example combines the motifs of Discovered Check, Fork, and Mate-in-Two!