Increasingly I find that all things are actually energy, either "mundane" or "magical". These two energies are clearly different, and seem to even obey different universal laws. Magical energy seems to hold sway over mundane energy, but there is still immense power contained in the mundane. A stick of wood, under the correct circumstances, will engage in a chain reaction that releases almost all of the stored energy within. Not all mundane objects contain the same energy density, and the same is true of magical objects.
Demon bodies are some of the most magically dense matter I have yet to find, except for the exceptionally rare "divine" artifacts. And of course the theoretical density of the "relic".
The explosion of a magica reactor is impressive, but ultimately a waste, in terms of destruction power. However if you could create a super dense magica and mundane object that could easily be triggered into a chain reaction?
A crude hammer, but perhaps one day I'll need such a tool.
-Notations filed under "errata" in the workshop of the Demon Master, The Head Master