Post your own-created chess puzzles here!

For those who haven't seen it, I have created a club for puzzle-interested people where you can share and discuss your and other people's puzzles. The club's name is The Problemists' club. There are currently very few members in the club, but I hope there will be more soon. Here is the link:

https://www.chess.com/club/the-problemists-club#:~:text=Support-,The%20Problemists%27%20club,-4%20Medlemmar

I have kind of run out of ideas for new puzzles, so I post a puzzle that I composed a couple of months ago:

At the end of the puzzle, black would really like to say: "Fork you!"

It has turned out that I actually haven't run out of ideas... at least not in the fairy problem world. Today, I composed this retro-puzzle:

Knowing that black hasn't promoted to a knight, can you tell the process that gave white that b8 bishop?

Look at the coordinates. White is playing upwards.

Okay, can you post your reasoning about the solution? BTW I missed to say that black has both castling rights left.

Okay, now I have no clue XD. I though Black promoted to a rook.

Okay then I thought Black took on g1 and made a bishop. But now i see what happened

This is very ineffecient, but it was me playing some ideas out.

Here is pgn

1. Nf3 Nc6 2. Ne5 Nd4 3. Nc6 Nb3 4. Nxd8 Nxc1 5. Nc6 Nb3 6. Nd4 Nc5 7. Nf3 Na6 8. Ng1 Nb8 9. h4 h5 10. Nh3 Nh6 11. Nf4 Nf5 12. Nh3 Nxh4 13. Ng1 Nf5 14. Nf3 h4 15. Rh3 Nc6 16. Nd4 Ne5 17. Rd3 h3 18. Rg3 h2 19. Nb5 h1=Q 20. Nxa7 Qh4 21. Nb5 Qa4 22. Nd4 Qa7 23. Nf3 Qb8 24. Ng1 Nh6 25. Rh3 Ng8 26. Rh1 Ng4 27. a4 N4f6 28. a5 Nh7 29. a6 Nhf6 30. a7 Nh7 31. axb8=B

Well done, @Sharp2Axe! I see though that you did not really post your reasoning. So I will do it instead.
White's b8-bishop is not white's original bishop, since it can't have come out when the pawns on b2 and d2 (their original squares) are there. So, the bishop is a promoted pawn. For the bishop to come to the dark square b8, it must have been promoted on a dark square. Looking at the black pawns, a white pawns can only have promoted on a8, b8, h8 and g8. A8 and g8 aren't dark squares (plus the bishop couldn't come out from a8). Additionally, due to the black g7 pawn, a bishop on h8 could not escape either. Since one of white's pawns has promoted, it's either the a-pawn or h-pawn. The h-pawn cound not come to b8, among other reasons, in lack of enough captures. 
Conclusion from this part: White has promoted the a-pawn on b8.To come to b8, white's pawn must have captured something on b8 when being on a7. It couldn't capture something earlier, because of the black c-and b pawns. So what has it captured? Black has both knights on, hasn't got a new one, and the e7 and g7 pawns mean that the bishop hasn't come out. Also, the e7, d7 and c7 pawns, along with the unmoved c8 bishop-and king, means the queen has been captured in its place. The only thing black could have hung on b8 is thus a promoted piece. Black lacks only the a-and h pawns, so one of these must have been promoted. White doesn't lack any piece except for the c1-bishop, which, if it were captured by a pawn, would need a black pawn on b2 or d2, and then a white pawn couldn't be there. So, black hasn't captured on b1 or g1, which means they have promoted on either a1 or h1. A bishop couldn't come from there to b8 due to the white b-and g pawns, so black has promoted to either queen or rook. A rook couldn't come to b8, and if the original queenside rook did that, black would no longer have the rights to long castling, which the diagram text says black has. So black has promoted to a queen on a1 or g1 and put it on b8 before white got the pawn up to a7 and captured it, promoting to a bishop.

What has happened: Black has got the a pawn and queen captured by white knights. Meanwhile, black's knight(s) captured white's c1 bishop and h-pawn. All knights have then returned to their starting squares. After that, black has put their h-pawn on h2, white has moved the knight and rook, black has promoted to a queen on h1, and got the knight to h7 and queen to b8. After that, white has advanced the a-pawnto a7 and captured the black new queen, promoting to a bishop.

I think that was all.

I composed yet another study a couple of days ago, and to solve it (or rather make sure white is really winning), you have to know the Troitsky line (you do, right?!), and here it is:

And here is the puzzle:

A bit hard?

It was quite ordinary in my opinion. Sure, not the most common, but it wasn't cool either.

I have had this puzzle idea for weeks, but first today I managed to compose a study on it. You'll see which idea soon.

OMGG THE UNDERPROMOTION !!

Here is a puzzle I composed today (which I'm 99.9% sure someone else has also composed):

I made my first puzzle, sorry if it's not perfect but I used suggestions from Coach

Nice try, @urfriendlymail4114. But I think it would have been even better if it was something like chasing the opponent's king down the board to a specific square, where it's mated. Also, a good puzzle should contain something suprising.

ok then, ill compose another one... (with something surprising) also my puzzle is in the middlegame not the endgame like the one you were talking about...

That was sadly even worse, since the solution wasn't even working. 1...Bf4 was a meaningless move, while 1...Qxd5 would be winning. And after 2.Bxd3+, white would be completely winning. Moreover, after 3...Re3, white isn't forced to take, and both Bxd3+ and Nxd3 would win for white. You have to make it work.