Genma didn't want just a simple Sage Mode.
If all he wanted was a simple Sage Mode, he could learn it from Senju Hashirama right now.
He was sure Senju Hashirama wouldn't refuse a genius young descendant like him.
And even if he couldn't sense Natural Energy, he could still spend a small amount of Setting Value to change the rules.
With his ability to sense Natural Energy, vast chakra reserves, and powerful control, mastering Sage Mode would be no problem at all.
But the Sage Modes of Senju Hashirama, Jiraiya, Yellow Flash, and Naruto didn't have the ability to nourish the body.
Once their Senjutsu Chakra was used up, their Sage Mode ended immediately.
That was clearly different from the three sages of the Three Great Sage Lands and the Sage of Six Paths.
Genma didn't know how they managed it, and he didn't need to find out. He only needed to change the rules and gain the ability himself.
In other words, he wanted to absorb Natural Energy to strengthen his body, much like how Wood Release Chakra was subtly changing his constitution now, gradually letting him remain in Sage Mode as his normal state.
Or, to put it another way, he wanted his body to become sage-like.
Or, like the God Tree and Tailed Beasts, he could directly absorb Natural Energy and convert it into stamina, then refine it into Senjutsu Chakra.
It was a promising path to immortality.
After setting the change, Genma immediately chose to apply it.
"Hm?"
Genma frowned.
The modification failed. Not enough Setting Value!
"Fifteen points of Setting Value still isn't enough? That's steep!"
Genma sighed and, after a moment's thought, settled for the next best thing.
If he couldn't do it all at once, he'd take it one step at a