How to reroll Retainers in singleplayer?

[Dark Sun Gwyndolin]

So, it's known that there's a way to reroll the random retainers that Generals and Agents get at every even level. However, I can't find out HOW. Searching Google just gives me useless stuff like "Here's a one-hour video with the trick somewhere in it", or "I'll tell you how its done once this thread gets enough responses."

Can anyone cut through the ambiguity and tell me how it's done? Apparently, it has to do with rerolling the RNG seed when you create a save file, but how is this done? Do I need to go back to before the battle where the unit leveled up, create a new save, fight the battle, every time I want to reroll? Or is there a more elegant solution?

[BastardSword]

For generals, what I do is make a save right before my general gets to the next level. Then I'll autoresolve a battle. If I get a crappy retainer, I'll reload the save and try again. You can try this with a general like Uesugi who can fight a rebel army twice on turn 1. Once any general has won two battles they go to rank 2 and get a retainer. Usually I don't bother with this but I know that it's a thing that you can do. I don't know if there's another trick.

As for agents, the trick to getting different outcomes is to move them differently before you order them to do their action. If you keep moving them the same way to do an action, they'll usually get the same outcome every time. If you move them slightly differently then you'll get a different RNG seed. Like if you have a 95% chance of success but keep failing, try moving the ninja or monk around a bit before having them kill or convert another agent. I know this affects the outcome but I don't know if this affects the retainers, I expect it would.

Anyway it is easy enough to experiment with, I think level 1 agents go to level 2 after 2 successful actions.