He was frantically pointing towards the glowing mountain. “We need to cast The Spell!”, Bothar screamed!
I held up the scroll we all had risked our lives to get. “Nobody can cast this spell without a prepared mystic space and ritual equipment. It would be suicide,” I said. “Not even him,” I jerked my thumb towards the Magi who smiled slyly.
Silently, he unstrapped that bolt of cloth he had been carrying since I had known him. He unfurled it, tamped it down, with small spikes, pulled a small apothecary chest out, placed and lit four candles on the cloth, drew some lines with some handy chalk, unpacked his remaining tools, then he held his hand out expectantly for the scroll. It took a fraction of a candle mark.
“Solomontic Rug,” he said quietly. “The key to mastery is knowing and having the right tools, be they physical, mental, or magical, and having them ready when you need them.”
A small, primitive village has yet to discover fire, which is a good thing because there are highly flammable (but not otherwise dangerous) gasses in the air. The heroes, blissful in their ignorance, don't know that and think it a wonderful idea to show the locals open flame.