Repeating. There is no need for this. Instead 71...Qhc4#.

I suspect we have just had a threefold repetition of position here. White could well have claimed the draw with his next move.

He could of. In fact, with a small mistake Caviyah, who's also a strong player declared a draw by repetition. There was no immediate mate either, but despite being ahead, I had my pieces tied down. Yet, white could've done the same thing here.

At last: progress!

Why not the OTHER queen? This one was the fence. Why move the fence?

Well played defence! Anything else would have been mate in one.

Moving the fence again! Why? That queen where it stood was doing the most useful work. The one twiddling his thumbs was the rook. Black had a mate in two, here, and all that was needful was to keep the essentials of the position 'as is' and force the W king to move to c2. Any of four rook moves on the a-file, or any move by the Black king would have forced Kc2 and ...Ra2#. Alternatively, the rook could have moved to e6. g6 or h6, and then down to the second rank to deliver mate that way. Or, Black could have played the queen to the second rank with check, and THEN the other queen from f3 to the first rank to deliver mate. I have counted eighteen possible moves from the previous diagram that offered Black checkmate on move 77.

One of the queens to c5.

Instead 79.Qgc5#

Instead 80.Qb1ch. Either queen. Or 80...Qb6ch. We've been here before. These back and forth checks are near-on useless. They make no progress at all.