pretty endgame tactic

[Event "Blitz:5'"]
[Site "?"]
[Date "????.??.??"]
[Round "?"]
[White "Rybka 4 w32"]
[Black "?"]
[Result "0-1"]
[SetUp "1"]
[FEN "6Q1/8/kb6/2r5/r7/3K4/8/8 b - - 0 1"]
[PlyCount "11"]
1... Rd4+ 2. Ke2 Rc2+ 3. Kf3 Rf2+ 4. Kg3 Rd3+ 5. Kh4 Rh2+ 6. Kg4 Rg2+ 0-1

[Event "Blitz:5'"]
[Site "?"]
[Date "????.??.??"]
[Round "?"]
[White "Rybka 4 w32"]
[Black "?"]
[Result "0-1"]
[SetUp "1"]
[FEN "6Q1/8/kb6/2r5/r7/3K4/8/8 b - - 0 1"]
[PlyCount "13"]
1... Rd4+ 2. Ke2 Rc2+ 3. Kf3 Rc3+ 4. Ke2 Re3+ 5. Kf1 Rf4+ 6. Kg2 Rf2+ 7. Kg1
Re1# 0-1