1. Solo Riou Requirement: Riou must remain the only active participant in combat for as much of the playthrough as possible. This means avoiding any additional party members in combat unless a storyline or game mechanic explicitly requires their involvement.

2. Limit Recruits to Auto-Join Only Only characters who automatically join the party through the storyline progression are permitted. Voluntary recruitment of any character, even those available early in the game, is prohibited. This rule adds an element of challenge by restricting party expansion to those members essential to the narrative.

3. No auto save or Save States: Do not utilize save states at any point, ensuring all progress is made through in-game save points only. This adds to the difficulty by making every decision, encounter, and battle outcome significant, as you won’t have the option to reload from a save state for a second attempt.

4. Critical Condition Requirement for Party Members Before Boss Battles: Prior to any boss fight, ensure all other party members, if present, are reduced to 1 HP. This rule raises the stakes, as Riou will need to handle the brunt of the combat, with any additional members severely handicapped in their ability to assist.