Been trying real hard to make comparison with martial cultivation stage Skin Toughening with Luke Cage's skin.
The Skin Toughening Stage is always:
Ox Hide (Leather): Minor Blade and Impact Resistant with Small Strength Boost.
Stone Skin: Medium, Medium
Copper/ Iron/ Metal Skin: Major, etc.
Then I realize, Luke is bulletproof, the ultimate Blade and Impact Resistant.
"Would the villains' superpowers be cool?"
Because oftentimes I see authors doing the whole "let's take a bunch of good guys' powers and mash them into my own fanfic SI"
I thought to myself, why not take from Dio or even Aizen? CN had someone doing that so...
And yes, I had seen someone here used Accelerator's and Mahito's power as their own SI before.