Mo Wuji was not foolish enough to think that this Unity God would follow him into his Grade 7 deathtrap array. The deathtrap array which he had set up was not entirely made of void runes. A Unity God, even with an ordinary level of knowledge on array dao, would be able to tell.
Moreover, this short Unity God's array dao was certainly not ordinary. If it was ordinary, he wouldn't have been able to destroy his void runes so casually.
The moment he entered the array gate, Mo Wuji's body trembled before disappearing into the thin air. In the next moment, an ordinary looking rock appeared at the entrance of the deathtrap array.
Mo Wuji had executed the Fetal Transformation Technique and in his first attempt, he managed to turn himself into a rock. This calmed Mo Wuji's mind and heart.
Every sacred art of the Heavenly Spirit Transformations had its benefits. Mo Wuji's choice of learning the Fetal Transformation Technique first was definitely a wise choice.