Question about CSB Amiga versions

[RogerS]

Hi,

Having just completed the Amiga version of DM, I've been looking into Amiga versions of CSB. I haven't been able to find an ADF version of CSB 3.5, but I found a WHDLoad version of it. The WHDLoad had issues when I tested loading a save state though, it would crash and display the message "Installed program has modified the VBR" so that's not an ideal option. I would preferably want to be able to use save states.

Looking in the downloads section here, there seems that there are a couple of cracked version 3.1 images that partially work:
http://dmweb.free.fr/?q=node/591

Does anyone know if the version cracked by Endless piracy only has the issue with the Vi altar but otherwise works perfectly? If so, that would acceptable to me because I don't intend to use any Vi altars anyway. If one of my champions dies, I'll just reload.

Does anyone know anything about the Odyssey version listed here?
https://www.planetemu.net/roms/commodor ... adf?page=C

Does anyone know of any other non-WHDLoad Amiga versions of CSB that work without any issues?

[ChristopheF]

Go to the shared OneDrive, browse to the 'Games' folder and download the file 'Chaos Strikes Back for Amiga 3.5 CTRaw.7z' that I just placed there.

It contains CTRaw images of CSB 3.5 (both the English only version and the Multilanguage version - both utility disks are the same) that someone shared on the English Amiga Board a long time ago.

They were dumped from original floppy disks (no cracks), and should work perfectly fine with WinUAE https://www.winuae.net/ and the IPF library at http://www.softpres.org/download

I have not played them myself (except a quick test), so please give them a try and confirm that they are indeed working perfectly.

[RogerS]

Thank you ChristopheF

I was about to post about how I just found a way to make a WHDLoad version 3.5 to work with save states after a bit of Googling, and trial and error. I have downloaded the file you provided though in case I run into issues with the WHDLoad version.

This is how it got it working with save states while using the WHDLoad version:
I installed lhasa (sudo apt install lhasa), then I extracted the files from the WHDLoad file to an empty folder "csbtest" I had created (lha -xw=csbtest ChaosStrikesBack\&EnglishUtilityDisk_v1.21.lha)

I then booted FS UAE with a Workbench 3.0 image in DF0:, the floppy image disk.1 in DF1: and disk.2 and disk.3 in the media swap list. I then checked each of the floppy images one by one and found out that disk.3 was the save disk.

I replaced disk.3 in the extracted folder with a CSB save disk I had made earlier on an ADF version of the CSB utility disk where I had imported my last save from DM, then compressed the extracted folder again as a zip file and loaded that file under "Hard Drives" in FS UAE.

In the "WHDLoad Arguments" field, I put "ChaosStrikesBack.slave NoVBRMove", and in FS UAE advanced settings I added the following:
relative_temp_feature = 1
unsafe_save_states = 1

I tested making a couple of save states at the beginning of the game, and there didn't seem to be any issues loading them again


I could try the Raw images you supplied as well. My worry though is that I might get halfway through the game or even further, and then find out that it's triggering the copy protection due to it maybe not being able to reproduce those fuzzy bits from the raw disk image, and thus losing my progress and having to start over. I'm not sure in which places in the Dungeons those copy protection checks come into place and what effects I would see if the copy protection checks fail.

[ChristopheF]

Trust me (I have studied the game source code), if the copy protection gets triggered, you will find out soon enough in the game. No chance of getting halfway withtout noticing it. Even so, if you have any issue, you can still load your saved game with another version of the game.

[RogerS]

By the way, I also found out earlier that I had to add the option writable_floppy_images = 1 in FS UAE, after I had tried to load my DM save ADF image in a different FS UAE config I made for CSB, only to have CSB say that there was no saved game found on the disk. It turns out that if you don't add that option, FS UAE will write the changes to an SDF file in the Save States folder for that configuration instead of to the actual ADF file.

[RogerS]

I did some testing of the raw English version 3.5 for about an hour, and can't say I noticed any issues in particular. I did notice that items that I threw at the sides of the room with the Executioner in it came flying back at me, but I don't remember having tried throwing anything there before, so I'm not sure if it's supposed to be like that or not. I didn't notice any issue when I tried throwing stuff in other places.

I didn't get very far in that time though, because I simply quickly picked up the dagger and paid the two coins for Storm (a weapon I normally don't bother with), just to have something to test with, and when I went to Supplies for the Quick to pick up a flask, I got blocked by a couple of Flying Eyes and fell down the pit. Instead of reloading I decided to just go with it since I was just testing anyway, but it meant that progress was slower due to no buffing potions and suboptimal weaponry.

I managed to kill a total of 4 worms, 1 flying eye, 2 munchers, 4 deth knights, 1 giggler, 1 dragon (which took a very long time) and an unknown number of mummies before I called it a day, still at the beginning of the Ku path. Didn't notice any issues (besides maybe the throwing thing in the Executioner room, although that might be how it's normally supposed to be).

Also at the very start of the Ku path, I intentionally dropped down a pit hoping I would land in the dragon room, but instead I ended up at "Surrender your possessions" and I had to drop my shoes.

Did I do enough play testing that I would have encountered any potential issues with copy protection?

By the way, I did notice that loading times seemed to be a lot longer when using the raw image and the CAPSImg plugin in FS UAE, like if I had set the floppy drive speed to 100% instead of Turbo (I did check in the configuration, and it was still set to turbo). That included when loading the save, which is on an ADF file. I did try booting from a WB 3.0 ADF in a different configuration to check if merely having added the CAPSImg plugin was enough to have disabled floppy turbo speed under all circumstances, but the Workbench disk still loaded at turbo speed.

[ChristopheF]

Executioner room: normal behavior, there are hidden teleporters that perform 180° rotation on objects in that room

Enough playtesting: yes, if you played 1 hour, moving between multiple levels and without triggering the copy protection, then you are safe. The copy protection is often triggered when moving from one level to another, and this happens very often while playing CSB

Slower floppy disk: I don't know about this, never did comparisons. Maybe this is required to emulate accurate timings that some copy protections rely on?

[RogerS]

After starting over again, I've noticed some weirdness going on in the area around Supplies for the Quick.

The first time, it was a red flashing Guru Meditation like screen, with the message "Chaos Strikes Back System Error 70. Press Left Mouse Button to Restart" after casting exactly two Dain potions in a row (drinking the first one right after making it of course), and it made no difference which character I did it with. The same would repeat itself any time I loaded either of the two save states I had made quickly in succession (I've started doing that to as a backup solution against corrupted save states) in the same spot, and I repeated the same action, I would get the same "System Error 70" message.

Then I loaded a slightly earlier save state, and looped around and picked up the second flask again. When trying to dodge a couple of flying eyes, I ended up sidestepping down the stairs to the room just below Supplies for the Quick. I turned around again while standing by the stairs and tried firing a couple of fireballs at the flying eyes, but nothing seemed to happen. When I turned around again, I got hit with the fireball damage for some reason, and when I turned around again, the fireball explosion graphic kept lingering on the screen as well as the damage numbers by the character portraits that the fireball had hit me with, and I also saw the flying eyes behind the persisting red fireball haze but they didn't seem to move at all nor did they attack.

I then proceeded to have Elija make and drink a healing potion, and after I had done the same with Chani, it crashed right after she had drank it with the same flashing guru meditation style "Chaos Strikes Back System Error 70" message.

I reloaded again, and looped around and picked up the second flask again and killed the wizard eyes. I then tested going up and down the stairs a couple of times, and the second time I went down the stairs to below supplies for the quick, I got a red flashing "System Error 60" message this time.

Does this sound like it might be copy protection that's being triggered?


By the way, if I set floppy drive speed to 800% in FS-UAE instead of turbo when using the raw image, it loads faster. It only seems to restrict the floppy emulation to normal 100% speed for raw images if I try to set the speed to turbo.

[RogerS]

After some more testing, I think it's safe to say that the raw image does not work (at least not in FS-UAE).

I've tried 800%, 400%, 200% and 100%, and I can reliably trigger the copy protection each time. I even tried changing the kickstart version from 3.1 to 3.0 (since I though I might have used 3.0 the first time I tested it) and tested that at 100% and at turbo, but it made no difference.

I did the following to test:
After loading the save, I immediately turned around and moved away from the worms while casting a couple of torch spells, and picked up one of the torches and put it in the wall sconce to open up the wall.

(In one of my tests, the wall wouldn't even open up by the way, even when I tried removing the torch and placing it back a few times. Shortly thereafter, it crashed with a blinking system error.)

I then ran through the run and jump section and killed the first flying eye with a couple of fireballs. I moved forward just far enough to where the door opened up, and waited a little bit to see if the one or two flying eyes that spawned showed up, in which case I would dispatch them with a couple of fireballs as well. I then ran back around the run and jump section again, picked up the flask then headed down the stairs.

I would turn around on the stairs a few times until I heard the disk being accessed, at which point I would try to cast another fireball. The fireball would get stuck in mid air every time after I had heard the emulated disk access sound.


It's strange that it seemed to be working fine the first time without any issues. I even did a bit more testing on that initial run, killing all the mummies, a few oitus upstairs (by going upstairs and immediately doing a berzerk with the with the Executioner or melee with the axe, then going back down as quickly as possible. I was having to do so multiple times, and I remember hearing the disk being accessed at least once when going upstairs to them), and all the vexirks in the room with the fountain. I even unlocked the secret passage with the chest in it behind the vexirk fountain room and went down to the dragon floor again from there. None of those actions seemed to cause any obvious issues on my initial test run.

[ChristopheF]

OK... strange indeed. Maybe using save states causes trouble with the copy protection? Have you tried playing without them?
I could check in WinUAE emulator on Windows to see if I get the same results as you do. Did you use the English or the Multilanguage version?

[RogerS]

I don't think it has to do with save states, because on my initial ~1 hour test run I later loaded from a save state and continued playing a bit more on that test run.

Also I can reproduce the issue reliably without using save states, booting from scratch and loading from the saved game from disk where I'm at the very beginning of the game in the dark and surrounded by worms.

The easiest way to reproduce it seems to be going up and down the stairs between supplies for the quick and the room below. Once I hear the disk being accessed, I then try to cast a fireball and it will get stuck in the air just in front of me.

I used the English version.

[RogerS]

I just tried with the multilanguage version and got the same result.

[ChristopheF]

I'm sorry that I made you waste your time with these disk images. I thought emulation of the copy protection would be fine with them.

[RogerS]

No worries Christophe. I'm grateful that you tried to help

Did you check in WinUAE to see if you got the same results as me by the way?

[ChristopheF]

I just did, and yes I get the same results.
I have checked the disk images with the 'Track analyzer' feature of HxC Floppy Emulator, and the copy protected sector has exactly the same content in each revolution (the CT Raw files contain 5 revolutions for each track). It should be different in each revolution because of the fuzzy bits.
That explains why the copy protection check fails and it also means that the image must have been dumped from a copy of an original and not an actual original as I believed.

Again, sorry for these bad images.

[m1ckey]

I'm sorry that I made you waste your time with these disk images. I thought emulation of the copy protection would be fine with them.

I did manage to finish CSB using real harware and the disk images you provided.

Wrote them back to real disks and used my trusty old 1988 Rev. 5 A500 0,5/0,5 RAM - KS 1.3

These are the images I used:

ChaosStrikesBack_Disk1of2 GameDisk_English
ChaosStrikesBack_Disk2of2 UtilityDisk_Supplied with English

Used the usual tips & tricks and spend like 30-40 min from start to finish without triggering copy protection.

I could´ve been just lucky?