When one hears about " forced entry, " images of open windows and broken down doors come into mind. It's essentially the same thing in the position on the left, breaking down barriers and creating havoc once inside the domain of the opposing king.
The black queen had just captured a pawn on a4 and the white queen countered with her own capture of a pawn on c3 with a check. The black king, who was on g7, had just stepped over to h7. What to do now for white?
Instinct alone will tell you that there could be a strong attack on the h file, and it could be very well be a successful one. As often is the case in the games I showcase on my blog, the positions stem from a 5/0 blitz game, no time to go into deep analysis. A quick survey of the position will tell you that black's bishop, knight and one rook are hemmed in, and the black queen is out of range if an attack on the h file does occur. The black queen does not have annoying checks to somehow get her back to the kingside. Lastly, there is also a couple of connected pawns in the center that white could steamroll through black's position. In spite of all this, material sacrifices on white's part were required to win the game.
I played 1. Rh5+. That was already obvious to everyone, but will the sacrifice work? Play continued 1... gh 2. Rh5+ , Kg6 ( forced ). The rook on h8 is now en prise, and so 3. Qh8 threatening mate with 4. Rg5# or 4. Qh6#. It seems that I was almost there for the kill, but alas not yet. Black took care of both these threats with 3... Nh7. Now, it was my queen that was hemmed in and I didn't want my attack to peter out. My rook was hanging as well, and I needed to keep the momentum going. So, I sacrificed a second piece with 4. Rh7, Bh7 ...and then 5. Bh5+!, sacrificing a third piece!!! Black declined the offer with 5...Kh6. If 5...Kh5, then 6. Qh7+, Kg4 7. Qh3#. The game continued 6. Qf6+, Kh5 7. Qg5#.
Post-game analysis revealed another winning line instead of the rook sacrifice on h7. The move 4. Rg5+ ( yet another sacrifice ) would also lead to a win via 4...Ng5 5. Bh5+ and all of the black king's options are covered.