I can't believe I missed this one!Game 1110044 move 12 for black
***No comments on the specifics of the game please as it is ongoing***
I think the "mother of all forks" would be King/Queen/both rooks. Never managed it yet, but King/Queen/Rook forks aren't unknown:
Game 1022261 move 16 black
Game 1065480 move 9 white