Main motif of this puzzle: Swallow's tail mate
In swallow's tail mate, a queen checkmates the king. The queen is orthogonally adjacent to the king. The king is not on the edge of the board. The two escape squares not guarded by the queen are blocked by its own pieces. A swallow's tail mate is also possible with a rook, when other pieces guard the additional escape squares.
Learn more in this guide.
The hint button is in beta test. We recommend to use the button only after you've thought about the puzzle for some time without finding any idea.
Read more about the hint button in this blog post.