Batman Returns
                         Anti-Antipiracy

                              

 v1.0, 17th of Feburary 2021


1) General Info
2) Patching & Compatibility with Other Hacks
3) Credits & Thanks



         
             1) General Info

This is a romhack of Batman Returns for the NES.

It gets rid of the numerous copy control mechanisms of the game.
The point is that other romhackers could use this hack as a base, and thus be able to modify the title
screen without fear of triggering the copy control mechanisms. 
Although to be honest, the main point was to take revenge on this stuff because it prevented me from 
beating the game in Nesticle as a kid due to a bad rom.


The copy protection in this game is probably the most nasty one Konami's pulled. It can do three different
things: double the amount of damaged recieved to the player (which also doubles the number of points added
to the counter which determines the ending you get), block the exit in stage 3-1 and thus make it loop,
hands out wrong passwords and makes it unable to enter any valid password. 


Here is the list of code that I disabled:
- In stage 2-2, when the Helicopter spawns, it checks for a part of the KONAMI logo. If it doesn't find it,
it triggers the copy protection flag.
- Later on in the same stage, in the part with electrified water, the enemies object handler check a part of
the Batman logo. If it doesn't find it, it triggers the double damage flag.
- In stage 2-3 (Catwoman bossfight), Catwoman's object handler checks for a part of the Batman logo. If it
doesn't find it, it triggers the copy protection flag.
- Another routine checks for another portion of the Batman logo. If it doesn't find it, it triggers the 
double damage bit.
- When entering a password, if the copy protection flag is set, all passwords will fail.
- On the continue screen, when being given a password, if the copy protection flag is set, the password
given will be wrong. For this one, I made sure the copy protection flags gets turned off if it is on, even
though there really should be no reason for it to turn on anymore. Just to be safe.
- In Stage 3-1, after having recorded the conversation with the Penguin and being back in the first street, 
the game checks if the copy protection flag is set, and if it is, makes sure that the exit window remains
closed and that the stage can not be completed. Again, I disabled this even though there really should be
no reason for the flag to be set anymore. Just to be safe.


             2) Patching & Compatibility with Other Hacks


Made for and tested with this rom:
Batman Returns (USA).nes

This hack is compatible with my other Batman Returns hacks: "Improved Controls" and "Bugfix & HardMode"
It *should* also be compatible with bad rom dumps, the ones that edited the title screen, therefore fixing them.

Using an IPS patcher such as Lunar IPS to patch the rom.
You can find the rom on archive.org.



             3) Credits & Thanks

ASM editing: MetHy aka Ness

Major thanks to Cah4e3 from TCRF, without his documentation I may not have been able to do this or it would
have taken a lot more time.

Thanks to the FCEU X devs.

Feel free to use this hack in your own hacks, no need to ask me, just a small credit is enough.