It's rare to see two top-tier Alchemists join forces in this world.
After all, top-tier Alchemists like Perfikot and Weir, who could lead an era, are exceedingly rare; so rare that an entire era might not see even one.
If not for a curse a hundred years ago that regressed Weir's age back to a young girl, she wouldn't have been able to survive these hundred years.
The Extraordinary individuals of this world are somewhat different from those in high-magic worlds. While their lifespan is indeed extended by becoming Extraordinary, living to a hundred-something years is the limit, and no one is known to live past two hundred.
Weir, despite being the most top-tier Alchemist of her era a hundred years ago, was not a cheat player like Perfikot; it took her half a lifetime to reach the Legendary realm.
So accounting for nearly a hundred years after suffering the backlash, if Weir hadn't encountered any accidents, even if she weren't buried yet, she'd be nearing the end of her life.