“And I looked, and behold a pale horse: and his name that sat on him was Death, and Hell followed with him.”
Revelation, Chapter 6, Verse 8
The following contains spoilers from My Hero Academia. You have been warned.
During the Paranormal Liberation War, we got a taste of what Tomura Shigaraki’s new power would look like after his surgery from Doctor Ujiko. However, his surgery was incomplete at 75% and he has not yet reached his full potential. Even so, Shigaraki was still capable of holding his own against multiple superheroes and cause unimaginable death and destruction. If Shigaraki can do all of that in his incomplete state, imagine how much more dangerous he would be when he reaches 100% completion. As hinted by the High-End Nomus, Shigaraki may be able to stabilize on his without the aid of his capsule. It looks like this was confirmed by the vestiges of One For All. Based on what the vestiges say, the future is going to get a whole lot darker than they already are. It looks like if Shigaraki reaches 100%, he will essentially become the ultimate evil. I don’t know if this means that All For One’s vestige will completely take over Shigaraki’s body or if Shigaraki and All For One’s minds merge to form a new being. In any case, this proves that Shigaraki is about to become an even more sinister supervillain. In terms of power levels, the One For All vestiges claim that no one would be able to stop him if he reaches 100%. This could mean that even if Deku can master One For All in its entirety, it might not be enough to take Shigaraki down. It might take the combined strength of all the remaining superheroes to take Shigaraki down. The only reason Deku was able to thrash Shigaraki as much as he did was for three reasons: 1.) Shigaraki’s surgery was incomplete, 2.) Shigaraki was at war in his own mind, and 3.) Shigaraki did not know how to fully utilize his newfound power. When Shigaraki reaches 100%, none of these limitations will remain and it will be a whole new ball game. To make matters worse, Shigaraki has an army of at least ten thousand supervillains he sprung from prison. Overall, the worst is yet to come for hero society as Shigaraki sleeps and accumulates his strength. When he wakes up, it will be Armageddon.