Library of the Ancients => Final Fantasy IV Research & Development => Topic started by: Pinkpuff on August 16, 2015, 07:02:49 AM
Title: Fixing FF4's "speedrun exploits"
Post by: Pinkpuff on August 16, 2015, 07:02:49 AM
Aznblusuazn has provided me with a list of the major bugs typically exploited by speedrunners. It would be nice if we had patches for these, as I think it would make the game better as a game, but at the same time, I'm hesitant to build them into, for example, Unprecedented Crisis, as there seems to be a speedrunning community that might not be so keen on playing it if these are fixed. Thus, I think these should be separate individual patches (or maybe a single "FF4 Bugfix Patch" akin to the one for FF6).
I don't have the skill to tackle these, but I figured I'd list them here in case anyone has the skill and/or desire to attempt it:
Mist clip: There's a way to use a tent mid-step to mess up the hit detection of the map. This can be used to walk completely over Mist village and enter from the back. Unprecedented Crisis detects and punishes this, but it's not a fix for the bug itself.
Item duplication: By equipping in a certain way mid-battle and then fleeing and re-equipping after battle, you can end up with multiples of an equippable item. You can also create multiples of the "blank" item this way and sell them for tons of money. I was linked to a document relevant to this, but again, I don't have the skill to tackle it: https://dl.dropboxusercontent.com/u/19404607/ff4/Dupe%20code.rtf
Raising a dead monster: By targeting a monster with a Life/Raise effect as it's dying, it won't respawn the monster, but it will still add an additional instance of its rewards after you win the fight.
Reacting to reflected spells: Monsters don't react to reflected spells and/or damage the same way they normally do. This means you can manipulate monster A.I.s in strange ways, such as killing the first half of the fiends without them changing forms by reflecting flare, etc.
MP Underflow: I forget how to trigger it, but in any case, you can somehow in the menu cause a character to have way more than their Max MP.
Warp stack: By continuously teleporting and building the warp stack up to 256 and then warping, you go somewhere strange instead of where you should go. This is determined by whatever's in ram where the pointer is mistakenly looking, such as vehicle locations, menu colors, battle speed settings, etc.
Title: Re: Fixing FF4's "speedrun exploits"
Post by: chillyfeez on August 16, 2015, 08:42:41 AM
I'm on the proverbial fence about the utility of such a patch.
The exploits listed here rarely, if ever, happen by accident. The only one I knew about before becoming a FFIV hacker was weapon duping, about which I think I heard from a friend at school who read it in a cheatcode book sometime before the widespread availability of the worldwide web.
The point being, "honest" players, for lack of a better term, are unlikely to ever experience these bugs/glitches/whatever at all, and speedrunners are unlikely to have any interest in a patch that fixes them. So while I might be able to create a fix for some of these, the bigger question might be, "who is the audience?"
Title: Re: Fixing FF4's "speedrun exploits"
Post by: Pinkpuff on August 16, 2015, 09:04:44 AM
Good point.
Title: Re: Fixing FF4's "speedrun exploits"
Post by: LordGarmonde on October 28, 2015, 12:41:51 PM
Aznblusuazn has provided me with a list of the major bugs typically exploited by speedrunners. It would be nice if we had patches for these, as I think it would make the game better as a game, but at the same time, I'm hesitant to build them into, for example, Unprecedented Crisis, as there seems to be a speedrunning community that might not be so keen on playing it if these are fixed. Thus, I think these should be separate individual patches (or maybe a single "FF4 Bugfix Patch" akin to the one for FF6).
I wouldn't mind seeing such a patch. Perhaps someday I'll have the time to sufficiently sharpen my programming skills to the point that I could tackle some of these. :blits: Though, at the same time...
The point being, "honest" players, for lack of a better term, are unlikely to ever experience these bugs/glitches/whatever at all, and speedrunners are unlikely to have any interest in a patch that fixes them. So while I might be able to create a fix for some of these, the bigger question might be, "who is the audience?"
I can agree with that too. My answer would be anyone who knows such exploits exist and it bugs them... :blush:
[/li] [li]MP Underflow: I forget how to trigger it, but in any case, you can somehow in the menu cause a character to have way more than their Max MP.
My understanding is that it has to do with a conflict of input between a directional and a button. It seems like when trying to use a spell that there's a frame between that selection and the check for sufficient MP that can be waylaid allowing the spell to be cast anyway.
Just as a reference I've added some links to speed runs and game breaking:
Title: Re: Fixing FF4's "speedrun exploits"
Post by: Bahamut ZERO on October 28, 2015, 02:40:04 PM
For what it's worth, I'm all for figuring out what causes the weapon duping bug (if it's not yet known in a technical sense).
I didn't know the "Mist clip" bug even existed - how does Unprecidented Crisis detect and punish this? Does it use the conditional branching hack at the Cecil in Kaipo event to warp immediately back to Mist if X flag is not set?
Title: Re: Fixing FF4's "speedrun exploits"
Post by: chillyfeez on October 28, 2015, 06:33:32 PM
Wow, hey, LordGarmonde. All sorts of folks we haven't heard from in a while are cropping up lately!
Title: Re: Fixing FF4's "speedrun exploits"
Post by: Pinkpuff on October 29, 2015, 05:38:52 PM
For what it's worth, I'm all for figuring out what causes the weapon duping bug (if it's not yet known in a technical sense).
I didn't know the "Mist clip" bug even existed - how does Unprecidented Crisis detect and punish this? Does it use the conditional branching hack at the Cecil in Kaipo event to warp immediately back to Mist if X flag is not set?
Actually the conditional hack wasn't needed; you can do this with a plain old condition check for which event to launch. Basically there's a trigger at the other entrance to Mist and another one at the entrance to Kaipo that checks the "Mist Events" flag. If unset, Zeromus has a few things to say to you ^_^
https://www.youtube.com/watch?v=komP3DFnKk0
Title: Re: Fixing FF4's "speedrun exploits"
Post by: LordGarmonde on October 31, 2015, 02:49:10 AM
Actually the conditional hack wasn't needed; you can do this with a plain old condition check for which event to launch. Basically there's a trigger at the other entrance to Mist and another one at the entrance to Kaipo that checks the "Mist Events" flag. If unset, Zeromus has a few things to say to you ^_^
https://www.youtube.com/watch?v=komP3DFnKk0
Nice; very clever. Same can be said about your hack overall. :wink: