The Ring Out mechanic had several scrapped iterations. These included being frozen, falling off buildings, and being consumed by animals when outside of the ring.
SNK created new assets for the loading screens on the Neo-Geo CD version. However, the art style used for said loading screens was considered "too eccentric" by many fans, to the point that they sent letters directly to SNK demanding that they shouldn't use the style anymore. Because of this, the art style used in those loading screens was never used again in future SNK games.
The team originally wanted to include a brand new character into the game. However, because of Billy Kane's popularity among fans, they scrapped this idea and added Billy instead.
This game was originally planned to be the final chapter in the Fatal Fury series, but the game was successful enough to dismiss this plan.
Cheng Sinzan was originally going to appear in the game as a playable character, but Duck King was chosen over him in the end.
The "ring-out" mechanic added to the game was heavily criticized by arcade players as it was possible to lose a match with only a single mistake such as blocking from an enemy attack, or side-stepping behind the enemy only to fall out. Because of this, the ring-out feature was removed from future games in the series.
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In the Neo Geo AES/MVS version of Real Bout Fatal Fury, Blue Mary can be seen topless if she falls into the water, this was cut in the PS2 version.