visayanbraindoctor: Phase 3.
Now comes the marathon part. I am very poor at Queen endings, which often resemble a bizarre abstract splash of chaotic colors for me, but I can get the gist of what is happening.
Alexander essentially decides that his King is too exposed on his King side, with only two pawns for cover. So he King marches to the Queenside where he has three pawns to cover his King.
37. Ka2 Qe8 38. Qc7 b5 39. Kb1 Qe1 40. Kb2 Qe6 41. b4 Qe4 42. Qd8 Kf7 43. Qf6 Ke8 44. Qd6 Qd5 45. Qf6 Kd7 46. Qg7 Kd6 47. Qf6 Kc7 48. Qg7 Qd7 49. Qe5 Qd6 50. Qg7 Kb6 51. Qc3 Qe7 52. Qd4 Kb7 53. c3 Qf7 54. Qh8 Kb6 55. Qd4 Kb7 56. Qh8 Qd7 57. Ka3 Qe7 58. Qf6 Qc7 59. Kb2
Once this is done, he now creates the all important passed pawn, but this time on the Queenside. His pawn structure on the Queenside affords better protection for his King
Alexander takes the plunge. He creates his sought for passed pawn on the Queenside but at the expense of uncovering his king to checks. He has foreseen this though and marches his King back to the Kingside in order to capture the White g5 pawn.
59... a5 60. bxa5 Qxa5 61. Qe6 Qc7 62. Kb3 Qf4 63. Qd7 Kb6 64. Qd8 Kc5 65. Qe7 Kb6 66. Qd8 Kc5 67. Qe7 Kd5 68. Qd7 Qd6 69. Qg4 Qc5 70. Qd7 Ke5 71. Qxh7 Kf5 72. Qd7 Kxg5
The purpose of these long king marches? It gives Black two mobile passed pawns.
Since his King, after his mission to capture the White g5 pawn is completed, is more exposed in the Kingside, Alexander than embarks on a King march back to the Queenside, his third lateral across the board King march! He knows that his King is better protected from checks on the side where he has two pawns rather than one.
73. Qd2 Kf6 74. Qd8 Kf7 75. Qc7 Qe7 76. Qf4 Kg7 77. Qd4 Qf6 78. Qe4 Kf7 79. Kb2 Qd6 80. Qf3 Qf6 81. Qe4 g5 82. Qh7 Ke6 83. Qe4 Kd6 84. Qd3 Kc7 85. Qh7 Kb6
With his king protected from perpetuals, Alexander than can make several moves with purposes other than to run away from checks. In effect he gains extra tempi. He uses these tempi to push his passed g pawn up and to place his Queen in a dominating position in the middle of the board.
Notice that the middlegame principles of central domination, initiative and tempi have come into play. From this perspective Queen endings are like complicated middlegames, and often should be played like one.
73. Qd2 Kf6 74. Qd8 Kf7 75. Qc7 Qe7 76. Qf4 Kg7 77. Qd4 Qf6 78. Qe4 Kf7 79. Kb2 Qd6 80. Qf3 Qf6 81. Qe4 g5 82. Qh7 Ke6 83. Qe4 Kd6 84. Qd3 Kc7 85. Qh7 Kb6 86. Kc2 Qf4 87. Qe7 Qf2 88. Kb3 Qd2 89. Qe8 Qd5 90. Kb2 Qd6 91. Qe3 Qc5 92. Qe8 Qf2 93. Kb3 Qf6 94. Qd7 Kc5 95. Kc2 Qe5 96. Qd8 Qe4 97. Kb2 g4 98. Qd7 Kc4
Putting his central domination and the fact that the White Queen has to guard his g-pawn over in the Kingside from advancing more, Alexander attacks White's King and remaining pawn on the Queenside directly. This nets him the last pawn and he is now three pawn up.
99. Qd1 Qg2 100. Ka1 c5 101. Qc2 Qf1 102. Kb2 Kd5 103. Qd2 Ke4 104. Qg5 Qf5 105. Qh4 Kf3 106. Qh1 Ke2 107. Qg2 Ke1 108. c4 b4 109. Qg1 Ke2 110. Qg2 Ke3 111. Kb3 Qd3 112. Ka4 Qxc4
Alexander shelters his King around his two pawn Queenside majority while pushing up his g pawn in the Kingside up to Queen.
113. Qg3 Kd2 114. Qf2 Kc3 115. Qe3 Kb2 116. Qe5 Qc3 117. Qg5 g3 118. Qg4 g2 119. Qg5 Qc1 120. Qc5 Qc2
I am sure that in the details, improvements for either players can be discovered by computers or by professional analysts, but above is the plot of the game as I see it.