While playing through the game over and over I stumbled across a way to duplicate items! There are some serious limitations and emulation users will experience more success as it requires luck manipulation. The glitch uses the "deals" option, so first I need to clear up mechanics about that. Then onto the glitch.
-There are 14 preset deals throughout the game (I will list them later)
-Each deal WILL be available for each playthrough
-To trigger a deal you simply check deals then exit the conversation. Talk again and check deals
-often a deal will show up on the first check. Almost never will you need to check more than 15 times if a deal is ready to be discovered
-Only 6 deals can be on the list. After that, the left most deal is erased. Deals enter on the right side of the list.
-A deal from a previous chapter cannot be discovered. Once it is on the list it can be bought later
If you have been diligent on checking the deals. At the start of the next chapter some of your deals may be duplicated and added to the deal list! It happens to 1,2 or none of the deals on the list. This glitch on is part of why anyone who has played this game feels that deals are inconsistent between playthroughs. However, proper understanding of this glitch can help you have 2 turbo peppers. Or 4 movement rings(agility rings). Maybe copy up to 12 power potions. Im in the process of trying to copy the Domingo Egg! Im not sure if attempting more than one Domingo will corrupt the game or not. So make a backup of your file just in case. Just fill your deal list with things you want to copy and if you have 6 items then dont put anything important in slots 1 or 2. The odds of duplicating one random item on your list is about 1/3. The odds of duplicating two items are about 1/12. Those are rough estimates. If your deal list is maxed out at 6 you will lose the left most items first.
One more point to clarify. The last moment the RNG spins is in the last dialogue right before the game asks you to save. I use character blinks. Darksol blinks but you cant see it visually. That's an important detail because saving when it asks and loading from there will not help you change the outcome. Cartridge users want to have a copy of their save BEFORE this point. Usually the last hit on a boss.
Here are the normal deals in any given playthrough:
Ch1 before battle 1 Doll hater
Before battle 4 jagged flash
Ch2 before battle 1 landslide
Before battle 3 zombie charm
Ch3 before batte 1 mermanbuster
Before battle 2 duelist
Ch4 before battle 1 repel ring
Before battle 2 elf slayer
Before battle 2 soulbuster
Ch5 ogre slayer
Chp6 before battle 1 sniper ring
Before battle 2 raging drum
Chp7 counter ring
Chp8 holy ring