Faraday cage, electromagnetic barrier, in this way, even if struck by lightning, the damage could be minimized, or even completely avoided.
But whether the lightning in this alternate world follows Earth's rules, even Lu Yu isn't quite sure.
The presence of Spiritual Qi might have some effect on the lightning, perhaps increasing its power, generating vitality within the thunder... it doesn't rule out the possibility of lightning breaking through the electromagnetic barrier.
It could be so powerful that it might directly melt the iron cage, and at that point, even with a Faraday cage, you couldn't stop the lightning strike.
Boom! A bolt of lightning struck, and another place lit up with firelight.
Lu Yu felt that he couldn't keep up anymore. He had just retrieved a piece of tree core, holding it in his hand while running and refining it, when he saw a new lightning-struck wood appear.
