1.
[
{B:8/8/6Q1/q7/k1n5/8/4P3/K2R1Nn1}
{V:It may seem odd to talk about visual effects in chess, but the whole basis of the game is geometrical and composers often strive to emphasize the element of visual paradox inherent in chess. The final position of this study is an excellent example of a purely optical effect. White to play and draw.;d1d2;Correct;That is incorrect.;Even White's first move is quite tough, but you should bear in mind a common method of defending against a kingside attack in over-the-board play, namely playing a rook to the second rank. In the later play Black appears to be making all the running, but White comes up with an incredible last-ditch defense.}]

2.
[
White's situation in the diagram appears to be utterly desperate. There are threats of mate by ...Qc3+, ...Qe5+ and ...Kb3+, and any kind of defense is hard to come by, for example 1 Kb1? Qb4+ 2 Kc2 Qb2+ 3 Kd3 Ne5+, 1 Ka2? Kb5+! 2 Kb1 Qb4+, 1 Qd3? Kb5+!, 1 Qc2+? Kb4+ 2 Kb1 Na3+ or 1 Rd3? Qe5+. The most tempting try is 1 Qg3?, but this loses to 1...Nxe2! 2 Qb8 Qc3+ 3 Ka2 (3 Kb1 Na3+ 4 Ka2 Qc2+) Qc2+ 4 Ka1 Qxd1+ 5 Qb1 Qd4+ and Black mates.]

3.
[
{S:d1d2}
1 Rd2!
Absolutely the only move. White would be quite happy for Black to take the rook, since 1...Nxd2 2 Nxd2 would be an easy draw, but of course Black continues the attack.]

4.
[
{S:a4b3}
1...Kb3+
Other possibilities aren't dangerous, for example 1...Qc3+ 2 Ka2 Qb3+ 3 Ka1, 1...Kb4+ 2 Ra2 Qe5+ 3 Kb1 or 1...Kb5+ 2 Kb1 Qb4+ 3 Kc1 Qc3+ 4 Kb1.]

5.
[
{S:a1b1}
2 Kb1]

6.
[
{S:c4a3}
2...Na3+]

7.
[
{S:b1c1}
3 Kc1
Certainly not 3 Ka1? Nc2+ and mate next move.]

8.
[
{S:a5c3}
3...Qc3+
After 3...Qc5+ or 3...Qc7+ White can simply run away with his king by 4 Kd1, but now 4 Kd1 would be met by 4...Qa1 mate. 4 Rc2 is met by 4...Qe1 mate, so it is hard to see what White can do apart from resign.]

9.
[
{S:g6c2}
4 Qc2+!!
Up to this point White has been desperately fending off Black's threats, but with this unusual sacrifice White takes the driver's seat, albeit at a heavy material cost.]

10.
[
{S:a3c2}
4...Nxc2]

11.
[
{S:d2d3}
5 Rd3
The consequence of White's previous move, but what about the apparently devastating response ...]

12.
[
{S:g1e2}
5...Nxe2+]

13.
[
{S:c1d1}
6 Kd1!]

14.
[
{S:c3d3}
6...Qxd3+]

15.
[
{S:f1d2}
7 Nd2+
An amazing position. Black has an extra queen and knight, but thanks to the oddly symmetrical grouping of his pieces he has taken away the only squares from the white king. Black has the choice between moving his king, with stalemate, or playing ...Qxd2+, when the drawn ending of king and two knights against king arises.]
