The Mu Lei Nascent Soul Dharma Image isn't just casting a single thunderbolt; the most basic thunder spell in the 'Yuqing Thunder Scripture' is a single-point thunder attack spell, relatively low in consumption but immensely powerful.
When Li Shiming cast the thunder spell, he activated the spell with five brains simultaneously.
Although he wanted to have a fair fight with Xiong Long, he didn't use the Heavenly Strike Thunder Hammer, his life-bound magical artifact, nor did he have any other thunder items, so he used five brains to compensate for the lack of help from thunder items.
The Mu Lei Nascent Soul Dharma Image continuously emitted thunder spells at intervals of a breath and three spells.
In the past, Li Shiming wouldn't dare use such a tactic, for the spiritual power within his nascent soul was insufficient, and he didn't dare to expend it this way.
