By refining and innovating upon Mount Myōboku's Senjutsu, they would no longer need to keep relying on Mount Myōboku when the time came. It could be said that the Great Toad Sage's actions were digging at the roots of their sacred land.
But there was no other way. The Great Toad Sage truly had no other choice. Uchiha Yue was different from Kaguya Ōtsutsuki. He was a man; he would not give birth to two Uchiha brothers like Kaguya Ōtsutsuki had.
The Uchiha Clan could already be considered destroyed. Uchiha Yue's ability was simply too unsolvable. The trait of being able to absorb all energy might seem simple, even ordinary, but once such an ordinary power possessed the potential for limitless growth, then no matter how ordinary it was, it became a power utterly beyond the reach of lowly creatures like them, who were bound by limits.
After so long, the Great Toad Sage had not seen even a shred of hope. One year... no, there was not even a full year left before this world was destroyed. When Kaguya Ōtsutsuki had descended back then, she had still left them more than a decade to wait and search. Time was simply too pressing.
They had to introduce a new variable. This was no longer the time to keep waiting for death.
Seeing the Great Toad Sage's resolute expression, Fukasaku and Shiken yielded. They knew that this was no longer the time to hoard their secrets. Even if it affected the future, there had to be a future first. If they could not overcome this calamity and deal with Uchiha Yue—
Then before long, everyone in Mount Myōboku and the Ninja World would die. What future would there be left to speak of?
To deal with Uchiha Yue, Senjutsu was useless.