The move-order 1.Nf3 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 would normally lead to the main line of the Kings Indian after 4...d6 5.d4, but instead 4...e5!? is a popular alternative, which leads to relatively unexplored positions.
Black sacrifices a pawn already on move 4 and does obtain quite nice positional (long-term) compensation by gaining control over the central dark-squares.
One of the main issues for White is what to do with his king. In the game Donchenko-Tomczak, White didn't find a good solution and got crushed in only 24 moves, though it should be said the game abruptly ended after White's blunder on the final move.
Exercise: What did he overlook?
A. Donchenko - J. Tomczak, Rubinstein Memorial, Polanica Zdroj 2022
Feel free to move the pieces on the live diagram!
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In every game of chess, there comes a moment when one is confronted with the question: what should I do now?

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