NOTE: This fix might not work for everyone. I am limited on data so I can't determine why it's like that.

• By removing annoying bugged quest items, I mean enabling them to be sold.
  
• I made a script to automate the hex editing process (which would be painfully slow if done manually).
  
• Spoilers = extra info. These are safe to skip reading.
  
• Completely read through "The Fix" section. Everything not contained in spoilers is stuff you should know.
  
• All other sections are background info/extra.

Then, preferably, move the save file that you want to edit into an isolated folder.

<steam installation directory>/userdata/<some number>/102500/remote
Tip: sort by date modified, descending, so your latest save appears at the top of the list.




I used Cheat Engine 6.6 for this guide.
If you are using Cheat Engine 6.7, step 4 will be a little different for you. (Thanks to Missilemike for his help in recognizing this important difference)
Cheat Engine has powerful automation with its Lua scripting engine; using a hex editor to edit files manually will be painfully slow and confusing.



Personally, I make 2 copies of the original save, and rename one of the copies to something like "12345save01.sav.bak" and then move the copy that I will work on to an isolated folder where none of the other saves are located. This way, if I pasted the isolated, edited save file back into the original folder and it replaces the original save, and then I find out that the edited save causes my game to crash on load, then I can simply rename the "12345save01.sav.bak" to "12345save01.sav" and replace the corrupted save.


Start up Cheat Engine (AS AN ADMINISTRATOR) and go to File -> Open File. Find and select your save. Be careful with what you do now, because any changes in file mode means that the change is written to the file instantaneously without any means to undo mistakes, hence the need for a backup file.
Really, if you don't believe me, just edit the value of the first byte of a copy of the save file and then close Cheat Engine without saving. Open the file back up, the edit is still there. Remember to restore the backup.

After the file is opened up in Cheat Engine (you won't visually see anything on Cheat Engine change except the text above the search progress bar will read "Physical Memory" instead of "No Process Selected"), press control+alt+shift+L to bring up the Lua Engine window.
Note that pressing control+alt+L (no shift) will bring up a similar Lua scripting window, and that is fine too.

Now, copy the code below and paste it into the Lua Engine window. It's a script that turns off the 0x80 bit of byte at offset 41 for every item [stack] in your inventory (continue reading the guide for more details). The in-game effect of this script is that it makes all items sellable.

Press the "Execute" button, and wait until the script finishes processing (it will print "done" to the output window when it finishes). You can close the scripting window and Cheat Engine now.
Now, depending on your version of Cheat Engine:

• Cheat Engine 6.6 and older: Changes are automatically written, so don't save. You can close Cheat Engine.
  
  
• Cheat Engine 6.7 and newer: You will need to manually save the file before exiting Cheat Engine.

• Your modified save is now ready to use. Make sure you place it back in the save folder before you start up the game.
  
• When the game starts, make sure to manually load the modified save. Pressing "Continue" might load an autosave that you didn't edit.

Now that practically every item that you own can be junked now, be careful to not mass destroy items in the junk inventory without checking for needed quest items.
I sell all my ex-quest items to my Gravehal Keep vendor; it keeps things tidy.

I haven't tested this fix completely, so perhaps there will still be a few items that may crash the game if they were tried to be sold/stashed/etc when they originally weren't meant to.

DOT NOT try to sell your reagent bag/alchemical recipes/component case/sagecraft pouch/key ring.

If your game crashes when loading the save, restore your backup save.

Quest items collected after you modify your save will not be able to be sold to vendors. Another run of this fix will be required.

If you want to make your own custom edits, here's the info to get you started down that path.

• Note: When it says constant/variable, it means that the values for those bytes don't change/do change respectively for every data structure that replicates this format (see description at byte offset = 8)
  
• Don't change anything that is labeled as constant.
  
• Bytes are numbered as if byte offset 24 and byte offset 43 both contain 00 (= false) so the data at 24+etc and 43+etc are treated as circumstantially required.
  
• The example used is an uncommon (green) leg armor with a might-based level requirement (greater than 20) that has 1 equipment bonus (+5% armor) and 2 sockets, nothing socketed yet, (haven't found the data for sockets yet), has a durability of 30/30, and is salvageable and sellable and stashable and whatnot.

At byte offset 41, this is where people have fixed their House of Ballads armor sets and such to be able to junk them. They changed 0x84 (binary: 1000 0100) to 0x24 (0010 0100).
This feels unsafe now that I have learned that this structure is used for both equipment and unequipable items; you wouldn't want to salvage a book and crash your game, huh?

We will be changing 0x84 to 0x04 instead (and 0xC4 to 0x44; we're just turning off the 0x80 bit). By doing this, it should enable the selling of those items.

Values I have seen for this byte: 0xC8, 0xC4, 0xC1 (Legend of Dead Kel building items), 0xC0, 0x88, 0x84 (example: House of Ballads set), 0x80, 0x48, 0x44, 0x40, 0x24 (example: salvagable equipment), 0x04, 0x01 (very rare), and 0x00.

Stuff I hope to find out later on:

• The bytes for buy/sell value
  
• The bytes for Might/Finesse/Sorcery requirements
  
• The data for sockets
  
• How weapons/armors/accessories/items/consumables/reagents/components/etc are differentiated
  
• The byte that differentiates common/uncommon/rare/unique/set equipment
  
• The byte or bit or whatever that determines if the weapon/armor/accessory is being worn or not (and if it is a ring, which slot)
  
• The byte or bit that determines if an item is stolen or not
  
• The byte or bit that determines if an item can be mapped to the radial menu (consumables)

Note that these things may or may not be found in the data structure table I listed.

Thanks to RenYue for his Kingdoms of Amalur Save Editor + source code.
Thanks to Raziel123x for translating the save editor + source code (mostly).
https://github.com/APK-Multi-Games/Kingdoms-of-Amalur-Reckoning-SaveEditer-PC
It would have taken me much longer to figure out how data in the save file was organized if I didn't have that code to reference.
Thanks to DarkByte for Cheat Engine.