On an OTB tournament I have recently played, I saw several mirages.
To justify myself - in the search for a beautiful combination.
Mirage No 1.
I am Black and 19. ... move was mine.
I knew I stood better. My opponent was a hopeless amateur, old pensionist who was delighted by his probably OTB tournament, clocks, writing the moves etc. I was blushing because of possible shame: what If I don't win?!
I shouldhave played by Queen without fearing capturing of my Rook> White doesn't have time for that.
But... I spent 35 minutes calculating "glorious" combination 19. ...Nxc4!!?
Mirage No. 2
I am White, it is 29.-th move, I have little more than 1 minute on the clock.
I played loosing 39. c5??
because I saw a "fantastic trap"
39. ...bxc5 40. bxc5Nb7 41. c6+ Rxc6 42. Rxc6 Kxc6 43. Nh5 ---
I missed the in-between check . ...Nc5 and Black can defend their pawns.
39. c5?? was losing because of 39. ...axb4.
39. bxa5 was supposed to hold a draw.
Mirage No 3.
I am Black on my 22.-nd move.
I wanted so badly to play 22. ...Ne3
and I was "calculated" for 45 minutes (!!), and I didn't see this:
22. ...Ne3 23. Rxa1 Rxa1+ (*I was dreaming of sacrificing the Queen, like Nezmetdinov... 😉---) 24. Rb1 Rc1+! 25. Qd1 Rxd1+ 26. Rxd1 Rxd1+ 27. Bf1 Rxf1 checkmate.
I dind't see 24. ...Rc1+
I played 22. ...Qa2?! and only after 23 Rb5 I played bad 23. ..Ne3??
I was in better position even after 22. ...Qa2?, but on 23. Rb5 I had to reply with Bf6, return a Pawn and then fight for the win "with other measures".
Mirage No 4.
I am Black and waiting for White's 28.-th move. I sat a 'trap" excpecting 28. f5? That's why I blocked a Pawn with Queen and opened F-line. (*I was fighting for whole point and I threw away even a draw.)
I saw the following mirage --->
On 28. f5?! I would have played
28. ...c5 based on the "calculation" 29. fxe6 Rxf1+ 30 Kxf1 Bb5+ 31. Ke1 cxd4. Here I stopped and was proud on myself. 😕 After 32.Bxd4 White has a huge advantage. Probably won position.
It didn't occur to me that I could have played this->
28. ...Rxf5 29.Rxf5 c5 30.Rxg5+ hxg5 31.Qd1 Rf8 and White has to play 32.Rf2 Rxf2 33.Kxf2 which gives my a little advantage.
Mirage No. 4.b
Little bit later in the game, White has just played 31. e6? and lost all advantage.
I "calculated" 31. ...Rf4 but after 32. Rxf4 I "realized" I don't have time for 32. ...Rxf4. I missed 32. ...Qd1+! which gives little advantage. That's why White shouldn't take Rook on f4 but move his Rook on the 1.-st row, which gives me opportunity for perpetual check with 33. ...Rf1+!.
I should have been satisfied with this.