Doing a soft reset after saving at a King resets RNG. This means that if you can reliably find a seed-dropping fight shortly after a save, you can repeat this to get many seeds quickly. This is a little more complex though with the RNG - in this video, you'll see that this is a two-cycle, in which I collect STR seeds with two alternating RNG starts.
I show off my Aliahan vault at the end. This method will also be done with Acorns of Life, and I think it is the ONLY way you can beat the game with no hero and multiple goof-offs.
I began this farming while all my characters are far away from leveling up. I believe the change in their stats my change the RNG.