[cradle] ranked spirit artifacts are a good shonen battle mechanic

people have ranks, but weapons can also have ranks

a weapon of your rank or below you can just use

one rank above, you can use if you're good, and it's difficult and costly

two or more, using it will PROBABLY kill you

so they can function like ults

an Underlord who has a kit of Underlord techniques and one Archlord weapon for emergencies

then as they rank up, not only can they use the weapon more reliably, but they can use its powers more effectively

Yeah, that's a solid worldbuilding angle.

right now Yerin is like

unquestionably stronger than Lindon

now that she has the Sword Icon

and now she has a hyperbolic time chamber