It took three days to get the materials ready, and for most of those three days my job was to stand out of the way.
I didn't mind. I had never watched people this good work this carefully, and I learned more from the corner of that laboratory than I had from a year of papers.
The Void Beast essence went first, because it was the most likely to kill someone. Master Valdris handled it himself. He worked inside a cage of containment fields so dense that the air around them rippled like heat over a road, and he moved the way a man moves around a sleeping animal he has no intention of waking.
"It doesn't want to be here," he said, without looking up. "That's the trouble with void material. Its natural place is between one space and the next. Hold it in ours too firmly and it tears. Hold it too loosely and it slips out, and takes whatever's nearest with it."
"Has that happened?" I asked.
"Once." He adjusted something I couldn't see. "We lost a wall."
