[Archilla]

Originally Posted by Krudelu

Spoiler for Context from a novel:

"Disappear! Dragon Blaster!"
BOOOM!!
The shoulder cannons fired releasing an extremely massive blast! Even as I tried my hardest to maintain my footing, I could not stop the impact from the recoil, and it sent my body backwards...! I used all my strength to stop myself from flying away!
The high output energy was fired into the midst of the Heroes Faction!
"Interesting, I will take this shot, legendary dragon!"
Heracles stepped up in front, was he trying to take my attack--
"Don't take it! Evade!"
Cao Cao yelled and used the base of his spear to hit Heracles away from the line of fire! Cao Cao and the other members then swiftly escaped my attack.
Without hitting anyone, the cannon blast continued flying onward far away behind them.
KABOOOOOOOOOOOOOOOM!
A large explosion shook the entire space while the city in the background was engulfed by the gigantic aura!
...The energy continued to spread, surrounding the entire city with intense light!
As the bright light faded, nothing was left! The cannon blast eliminated the entire scenery, and even the game field was affected and the artificial dimension began to show signs of distortion!
"...Destroyed the whole city! Hey! If he keeps firing, this dimension won't last!"
Heracles finally understood the power of my cannons, and cried out in surprise.
"Distorting the simulated dimension, yet this place was constructed to be sturdy... What kind of firepower was that?"
Siegfried stopped smiling and narrowed his eyes.

So at low end its at least city buster (Kyoto size).

It's easy to say that the DC can be more than that since it also cause distortion in the dimension made by Dimension Lost. If we factor in the dimension boundary (if there's one since from what I recall it only replicated Kyoto), maybe the boundary limited the expansion of the gigantic aura so I can see why it can be Large city buster.

Yep. That's the exact reason I added the +. It basically means it's even higher than the threshold, but not quite island level.