While writing this trilogy, I wrote the mages as I have always seen magic users: as pulling energy from their surroundings to cast spells. This is not how it is in the RPG Contagion, but the inventor of the game let me do it. Which was awesome.
From Inside the Grey House:
“I need to move her.”
Vincent moved forward and knelt beside his woman. “Where?”
Lilly looked around, eyes closed, trying to find…and there it was. “Your office.”
The healer lowered Natalia to the floor then stood and ran to the office to prepare it. Vincent slipped off his jacket, bundled it up and pressed it to the hole in Natalia’s stomach. He snapped his fingers and held out his hand to Joseph. It took a second for Joseph to understand, but then he slipped off his own jacket and handed it to his boss. Vincent slid the folded jacket under Natalia and rose with his lover in his arms. He carried her silently, swiftly to his office, her words echoing in his mind.