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[Atomic] Is this position win for black?

I need some help.
I analysed this atomic game:


This game was drawn, but I think black can get out of check by these moves after the last position:
1. Rf6+ Ke5 2. Rf5+ Ke4 3. Rf4+ Kd3! 4. Rd4+ Ke3 5. Re4+ Kf3 6. Rf4+ Kg2

Diagram after 6... Kg2:
lichess.org/editor/8/p7/1pp5/8/P4R1p/8/6kK/3q4_w_KQkq_-

I guess black can win in this position by using white's pawn, but I'm not sure because it's too complex.

Can anyone understand this ending perfectly?
It is quite complex. From what I understand, black needs to get rid of white's rook and generate another queen (2q+k vs k is a win in atomic) but I was thinking as long as white keeps his/her rook connected to the black king, that is very difficult.

My theory: because of the white rook's position on the f-file, black can never escape out with his king (Kg4?? Rf4+)in order to make white's king a checkable target, no matter how many queens black creates. While white's king is near black's, which is restricted to the g-file, it is safe.

Maybe someone can refute my theory.
It seems you don't need the white pawn to win - if you exchange black queen for white rook (seems to be easy) and promote three black queens you can win with zugzwang
But how would you take the rook away from the black king?
7. Rf2+, Kh1 8. Rg2, Qg1 and it seems that the rook will soon have to go away... what do you think?
Yeah, you might well be right, I can't see anything that keeps the king trapped any more with your moves.
It's not just about taking the white rook away from the king, you also need to make sure you can catch the white rook and not just chase it around the board endlessly. And for that you need more than 1 queen.

Fortunately I think 3 queens suffice to hunt down the rook (exchange R for 2Q), and an extra pawn/queen ensures there is sufficient material left to mate. The procedure should be something like this:
1. Immobilise white's king by putting a queen next to it, trapping it next to your king (best to be on h1) in the corner.
2. Get rid of white's pawn, promote all 3 queenside pawns.
3. Get into something like this, white has very little chance to stop you: lichess.org/editor/4R3/8/3q4/8/7p/2q5/6qK/7k_w_-_-
4. Now that your queens are controlling lots of squares, just hunt down the rook by confining it to the edge of the board directly. 3Qs can control all the squares along a rank/file, positioning themselves directly in front of the rook to prevent it escaping. e.g. from the diagram I gave, 1...Qcb4 2. Rf5 Qdf4 3. Rh5 Qfg5 and it's quite obvious the rook will be trapped.
5. If the white rook is on g1, trap it by playing a bQ to the first rank. Even (wRg1, bQf1) is winning, forcing Rxf1 and black still has Q+P, sufficient to win.

3Q can hunt down a rook, but 4Q are needed to win because it takes 2Qs to be exchanged for a rook. (e.g. trapping a rook on a7 with queens on b7, b4 and b2 allows the move Ra3, taking 2 queens with it.)
White can simply check forever on the f file. White should never play Rd4+?? If the rook continually checks on the f-file black can never escape the checks.
Instead of 4. Rd4+ what would you do? 4. Rf3+?? Qxf3 is a clean win. Before the pawn promoted it was drawn, but now that the Q guards f3 white's in for it.
Thank you for many answers.
I didn't know a basic knowledge: 2Q+K vs K is always a win in atomic...

#7 What a wonderful solution...

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