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>Your head still pounding, you realize using magic to investigate the cube further might be worthwhile
>You fear that initiating magical contact with the cube could disturb it and trigger a dangerous event, or corrupt your own magic in some incomprehensible way
>You carefully trace around the entire perimeter of the room, looking for any small nooks, crannies, tools... Anything whatsoever that could give you a clue, or aid you in your attempt to escape
>You find nothing. Nothing except for the glossy, sterile, white walls and floor caging you in like a helpless little bird. Or more accurately, like a helpless little unicorn.
>Nothing except for that foreboding cube, of course...
>You steel your resolve and channel magic into your horn
>It feels weak, and it causes your head to hurt even more
>Even so, you had trained in sensing-magic quite thoroughly, and became very efficient at doing it without much magic loss
>Your magical energy slowly envelops the cube in the shape of a sphere
>You make sure to not touch it directly, trying instead to gauge how much magical energy is stored within by sensing its flux across your own magic barrier
>You get an answer straight away: lots of energy. Lots.
>You're stunned that that much energy can remain stable in such high density without collapsing in on itself. Your knowledge of magic indicates to you that this shouldn't be possible...
>You dissipate your magic sphere, trying to avoid excess contact with the cube's aura as much as possible.

>Next, you try to analyze the hum coming directly from the cube
>Your horn fills with magic again and you close your eyes
>In the darkness, you begin to see the humming noise visually, pulsing up and down, up and down
>Your magic sweeps across the hum's frequency spectrum, from which you immediately notice it is in fact a rhythmic pulse
>You note to yourself that pulse wouldn't be the right word exactly, more like... a periodic series of undulations.
>You can see it consists almost entirely of very low frequencies, the majority of them not even perceptible to pony ears
>You stare some more at the magical display generated, but can't seem to decipher much else from it.

>You open your eyes, the cube still spinning in front of you
>You consider attacking it with whatever magic you can muster, but quickly decide against the idea
>Through your magical analysis you discovered that your earlier fears of disturbing the cube were justified: any serious magical perturbation could rapidly cause the energy held within the cube to become unstable
>You fear you may have no other option but to do the unthinkable...

>You shudder.

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