Draco was understandably surprised by Loving Aunt's assertion. "Any external source of energy can be used? So, electricity, kinetic, potential, light, heat, and others?"
Loving Aunt nodded. "Even life energy. However, as I stated, the cost of this is almost a thousand times greater than what would be needed for bloodline energy."
"Not only that, but this also depends - once again - on your Serpentine Familiar. Mine is a Blue Underwater Adder, the embryonic form of the Leviathan, which is a God Serpent."
"As such, the price I had to pay was really high, but I still managed to gather enough external energy for it."
Draco remained quiet for a few seconds before he asked the most prudent question. "What type of energy did you use for the technique?"
The serious and amiable aura around Loving Aunt froze, becoming something sinister and evil in a split second. The change was so fast that even Draco and Riveting Night were slightly startled.