Final Fantasy III: Game Over

This patch fixes a game-breaking bug that is triggered when the player dies 52 times in a row on the world map. The reason for this is that the Game Over event script calls an event that causes the player to exit the current location, which is the blank map for the Game Over screen; this script is the only script that calls the event. However, a side effect of this exit event is that the subsequent event, a return statement, never gets called.

The game uses an event pointer stack to handle event scripts that call each other as subroutines; when a script is called, the stack increases in size, and when a script ends, the stack decreases in size. Since the return statement at the end of the Game Over script does not get called, the stack does not decrease in size, meaning that a significant number of consecutive Game Overs will cause an overflow that will crash the game or worse. This only applies as long as the player is on the world map, as any entrance to an important location will cause the stack to regulate. This patch ensures that the exit event also regulates the stack.

Final Fantasy 3 (US/SNES), Final Fantasy 6 (JP/SFC)
Game Over Glitch Fix patch

CONTENTS:
FF3-GameOver-H.ips: The fix patch for a headered SNES ROM file. Apply to fix the Game Over Glitch.
FF3-GameOver-HR.ips: The reverse patch for a headered SNES ROM file. Apply to reverse all changes made by the previous patch.
FF3-GameOver-N.ips: The fix patch for a non-headered SNES ROM file. Apply to fix the Game Over Glitch.
FF3-GameOver-NR.ips: The reverse patch for a non-headered SNES ROM file. Apply to reverse all changes made by the previous patch.
FF6-GameOver-H.ips: The fix patch for a headered SFC ROM file. Apply to fix the Game Over Glitch.
FF6-GameOver-HR.ips: The reverse patch for a headered SFC ROM file. Apply to reverse all changes made by the previous patch.
FF6-GameOver-N.ips: The fix patch for a non-headered SFC ROM file. Apply to fix the Game Over Glitch.
FF6-GameOver-NR.ips: The reverse patch for a non-headered SFC ROM file. Apply to reverse all changes made by the previous patch.
readme.txt: This file.
Game Over.asm: An assembly format index of the code changes.
Game Over.txt: A text format index of the code changes.

ALL PATCHES WORK ON VERSION 1.0 OR 1.1.

PURPOSE:
There is a flaw in the code for one of the event scripts used in this game, namely the script that handles a Game Over. The faulty event is used to exit the player out of the "Game Over" screen so the game can continue from the last Save Point. However, a consequence of the event is that the next event, a return statement, is skipped. The return event ends all event scripts because the scripts are called as subroutines and the event pointer stack gets filled. When the return event is called, values are pulled from the event pointer stack to make room. However, because the return event is skipped at the end of the Game Over event script, more values are pushed to the event pointer stack than pulled, meaning if enough Game Overs happen, a conflict occurs in the RAM that can lead to a crash or worse. This only applies to the world map because in locations such as Cyan's Dream World, the stack is regulated.

Since the exit location event is only ever used in the Game Over script, the easiest solution was to modify that particular event to also reduce the size of the event pointer stack. This fixes its behaviour on the world map without interfering with its behaviour in dungeons.

Final Fantasy III (USA)
CRC32: E969BD77
MD5: A684517EBD29308C2E3B55D371E15245
SHA-1: 23422176191B371F01AE3A7CFE7455A2022F8EE8
SHA-256: 6F6911ED4A0E9844770035A3C39157F8C3929C321D5AFACBAFDA39C835B44374
Includes patches for headered and non-headered ROMs
Includes patches for SNES and SFC ROMs