"The greatest risk of the Blood-Exchange Art is blood clotting!"
"When spirit blood is used to replace one's own blood, unless the Water Essence Formula catalyzes the exchange, the mercury essence within the spirit mercury will merge into the blood, forming clots that are difficult to dispel."
"Even at the peak of Qi Refining, widespread blood clots throughout the body will prove fatal. Remember this, all of you. Remember it well."
The warning Master Artisan Bu had stressed during his lecture still echoed in Li Chen's ears as he sat inside the Water Spider, taking three hundred Host Insects toward the demon chief.
He had no other poisons at hand. The only thing he could use was spirit mercury, a consumable needed to perform the Blood-Exchange Art.
Back at the Octagonal Fort, Li Chen had purchased some related materials to study the art. He had never imagined he would end up using them here.
At his current level, refining spirit mercury suitable for use in a human body would still take considerable effort.
He had devoted most of his time and energy to the Potter Wasp Core and refining floating gold to keep advancing his cultivation, so progress in other areas had been extremely slow.
What he needed now, however, was not a safe, usable product with its side effects reduced to a minimum, but a crudely made substance that could poison demons to death without consequence.
The mechanism had limited capacity, so he could not fill it with much spirit mercury. He could only divide it into several portions and inject them fully through the needles, successfully slipping past the demon chief's senses.
Ordinarily, even low-ranking demons were exceptionally sensitive to outside harm. Those with powerful physiques could control their own blood and prevent harmful substances from spreading,