Gilmoy: Almost a Swinging Gate! Game Collection: The Swinging Gate: Push That P to 6 or 3!It lacks the pawn double-check, hence it works only because White had no overprotection of g2. (Deep/Silly: because it's KID racing, and White was elsewhere on the Q-side, haha.)
The Arabian on f1 is not merely picturesque: it provides a very useful generalization of the swinging gate pattern. Namely, a triangle mate in the corner presumes that you've trapped the K center-ward, so that he cuts off his own back rank support. Analogy: eclipse, with his back-rank R as life-giving sun, him as Earth, your R as moon. Then a triangle mate is normally a <lunar> eclipse: he's in the way. Equivalently, he has <half->weak back rank <from one side only>, and you're invading thereat.
Now flip this around, e.g. select the 3 columns of your mate pattern, spin them 180 around the g-file axis, keep everything else the same. Now we have a <solar> eclipse: your R feels the sun's heat, i.e. he has <not-weak back rank>. Does the pattern still mate/win? Here, we see that it mates if you have other support that overpowers the back rank protection: the Ne3 is ideally placed to protect g2 <and> underpromote to an Arabian.
So, we generalize: P on 3, Q sees 2, it's <still> a pattern-match, hence worth a quick think. We graduate from <never> seeing/considering this sac, to <always> seeing it in a flash, and idly doodling it in our heads 5 moves in advance. Quickly reject it because it has elements not satis -- zhemoi!! now we are rock stars
Kibitzing
