(Aw, I didn't think I was being that ambitious. Ah well, the end result is fine by me for now.)
Oh! There was much hardship for the Wretched People. They cried out for their creator, but the Crone turned her face away from her failure. She gazed outwards into the Planes and knew what was to be done...
-Dirge II: IV, from The Black Book of the Crone, The Last Age
[X] The Crone circles the universe and reaches into each Plane. Her talons snap off a piece from the heart of each realm and toss it into her cauldron. From the Plane of Shadow, a shade of darkest night; from the Eternal Engine a still-turning gear; from Iavodell a drop of abyssal waters; from the Worldmind a small yet terrible truth; from Chaos something wild and ever-changing; from Conflict a bitter anger; from Nothing, nothing; from Death, a scrap of the first dead thing's essence; from Fire a steady-burning flame; from Stone a fragment of Primordial Stone; from Air a gentle breeze - all goes into her cauldron. Once finished, the Crone retreats into the Forge and begins to grind together all that she has stolen. She laughs as she works, something taking form from the cruel caress of her talons.
The shaping complete, the Crone plucks out the first of her creations and holds it to the light. This is an orb of swirling shadows, no larger than a mortal hand, and it whispers of darkness and fading light. The Crone sees that it was good and much pleasing to her eye - but she is a creature of whims, and tosses it over her shoulder into the currents of Iavodell to be carried who knows where. It is followed by orbs echoing the power of every other Plane, until the Crone has shaped and discarded eleven Planar Orbs. These allow a living thing holding one to channel power directly from its respective Plane and gain control over that thing or element. Over time, they also change the user towards the nature of the Plane itself. For gods, the influx of power is insignificant, a drop in an ocean, but for mortals it provides vast abilities when mastered. Of course, channeling too much at once from a Plane will surely kill the user, and only the mad or truly formidable would attempt to claim several at a time.
TL;DR: The Crone creates elemental orbs from the essence of each Plane. These Planar Orbs grant their holders power over that element or thing and allow them to channel the Plane's energies through themselves. The Orbs are tossed into the currents of Iavodell to be carried off to who knows where, to be found by whomever.
Basically, creating some Rings of Power/Infinity Stones/Plot Objects for the world to come. Seemed like an appropriate way to end this Age.