No Conservation of Energy: Averted, dammit, despite the best efforts of generations of mad scientists to rip physics a new one on this point. (That, and the rest of the laws of thermodynamics. Well, mostly those, as the Empire has a lot of people running around who take the second, and to a lesser extent the third, laws of thermodynamics as something of a personal affront.)
This is a companion discussion topic for the original entry at https://eldraeverse.com/2015/04/06/trope-a-day-no-conservation-of-energy