What is needed is a large amount of Divine Sense, wood-series Spiritual Ink, and a high level of Formation mastery.
Even because Mo Hua was the one Drawing the Formation, he could even use "earth" as the Formation media.
This is the mysterious aspect of Formations.
It is also the strength of a high-level Formation Master.
The Wood Revitalization Formation, Mo Hua had learned long ago.
His nature is that of a "formation fanatic," with a strong curiosity and a thirst for knowledge.
Whenever he saw a Formation, he wanted to acquire it. Every Formation he acquired, without exception, he wanted to learn.
This Wood Revitalization Formation was naturally no exception.
Though it is an obscure Medical Array, for Mo Hua, who practiced with "Ultimate Formations" daily, it wasn't too difficult.
Mo Hua actually learned it a long time ago.
But he never healed people, so the Wood Formation had never been used, and Mo Hua didn't know whether it would work or how effective it would be.
