The Polish Defense is not an Unorthodox Opening. It is part of the Queen's Pawn Game. This variation of the Polish Defense is the reverse of the 1...d5 variation of the Polish Opening. Just like the other openings I have gone over, this opening has often been considered bad since it allows white to seize the center with 2.e4. What players do not realize is that this is the idea of the Polish Defense. Black allows white to have the center for a moment and plans to assault it later.
At first look, the Polish Defense looks just like the St George Defense with a different order of moves. White could play 2.e4 and after 2...a6, the position is the same as the St George Defense. The difference is that black does not have to play 2...a6. Instead, 2...Bb7 can be played.
Black has another, less risky, option in how to approach the Polish Defense. Black can first play 1...Nf6, and after white plays 2.Nf3 or another common move aside from 2.c4, black will then play 2...b5.
These lines offer black much better chances for the obvious reason of white not being able to play e4.
The Polish Defense can also be played against the King's Indian Attack.
Black gains queen side space and challenges white's bishop on the a8 to h1 diagonal. Black will play positionally against white with c5 and d6. Occasionally, black will even fianchetto the other bishop to control both colors in the center from afar.
And this concludes my overview of the Polish Defense. If any of you have other ideas for white or black, please comment. I would very much like to read other possibilities.