EDIT: I think a better name is gg chess, because "gg" (good game) is what folks frequently say at the end of a game.
At major chess events, at the end of a drawn game, the players & arbiter arrange the pieces in the following illegal position, to indicate that the game is over:
[Title "'gg game drawn' game array"] [FEN "rnbq1bnr/pppppppp/8/4k3/4K3/8/PPPPPPPP/RNBQ1BNR w - - 0 1"]
Now the FIDE movement rules still work in many illegal positions, and this is one of them. White to move is explicitly disallowed from capturing bK (which would in any case be a bad idea because then White could never deliver mate) and so must retreat out of check to d3, e3 or f3. It's now Black to move, with 26 or 27 choices.
Presumably 1. Kf3 is best, because it doesn't block White's central pawns. Black is no longer in check so may now be more aggressive, but alternatively "Petroff's retreat" (1. Kf3 Kf6) may become popular.
Generally this new starting position may address two long-standing gripes: first by reducing draws, and second by giving Black what may be a compensation for playing second.
Can anyone contribute any other opening theory or assessment for this new format, "gg chess"?
BONUS: there is a unique helpmate in 2.5 here! I.e. if the players co-operate, how does White deliver mate on the third move?
MORE: If the position is a White win, the kings go on wKe4, bKd5 and if it's a Black win, the kings are on wKd4, bKe5. (The pattern is that both kings are on the colour of square of the winner.) See this chess.com discussion.
I guess this is so that someone wandering up to a now-empty table can see what the result was. So that's three times the theory!
Does any arbiter have a formal FIDE statement that details this fun policy, please?
AND: In one of these three starting positions, if White plays 1. Kf5?? it's so bad that Black has a forced mate in 7. Can you find it?
[Title "'gg White won' game array"] [FEN "rnbq1bnr/pppppppp/8/3k4/4K3/8/PPPPPPPP/RNBQ1BNR w - - 0 1"]