This was not the spell that Merlin taught her; Piscel was hiding her true skills.
After the tree was drilled through, that destructive power made the leaves fall down.
However,
Before those leaves touched the ground, the knife in Piscel’s hand quickly swung and pierced them.
BANG, BANG! BANG, BANG! BANG, BANG!
Excitement emerged in Merlin’s heart.
Not only did he hear the sound this time, but he also saw the motion clearly when he kept his eyes on Piscel’s movements.
Piscel thrust the knife twice in a split second.
There were overlapping attacks!
An understanding appeared in Merlin's eyes, shining brightly.
“In one attack, she thrust the knife twice. They were two stabs with frightening speed. The two thrusts appeared at the same time in a split second. No wonder her power has doubled.”