Bertholdt was the owner of the Colossal Titan, a behemoth towering at sixty meters who was capable of destroying Shiganshina's walls and ushering in an invasion. He was one of the strongest character in the Attack On Titan universe, only defeated through the teamwork of Eren and Armin.
However, the God of Destruction's potential is limited through the few instances where he's had an opportunity to unleash his true form. Through placing him in a number of different anime cities and assessing how he would fare, we can better assess the power at his disposal.
10 Could Destroy: Alabasta Can't Use Its Best Weapon (One Piece)
Alabasta was a desert city with an extremely militant populace. Should its rebels and loyalists come together, they would form a decently sized army for any who would threaten their home.
However, without ODM gear or noticeable artillery, their meager weapons would fail to damage the Colossal. The only hope the desert nation would have is if they used the superweapon within their crypts. However, given that Nico Robin is the only person able to translate it, they are destined to suffer a fiery death.
9 Couldn't Destroy: Konoha Has Too Many Talented Shinobi For Bertholdt To Deal With (Naruto)
Most Naruto characters would struggle to defeat Bertholdt on their own merits. Even the most seasoned Hokage lack the firepower to topple a sixty-meter foe.
However, Naruto himself is an excellent exception to the rule, especially when his skills are complemented by the other shinobi of the Leaf. Sasuke would be particularly instrumental in bringing Bertholdt down because his Amaterasu will continue to burn and spread into it consumes its original target entirely (as proven through his fight against Killer Bee).
8 Could Destroy: Yorknew City's Best Defenders Are Barely Stronger Than Average Mobsters (Hunter X Hunter)
Yorknew City was the home of many crime families. They would converge for an auction intended to build congeniality and demonstrate their organizations' respective powers.
When the Phantom Troupe attacked, their greatest weapon was the Shadow Beasts, a unit who failed to defeat even Uvogin. Given how vastly Bertholdt's strength surpasses the villain's own and since the Zoldyck family would not be able to come to their defense in the blink of an eye, the Colossal would be able to destroy Yorknew well before its assassin saviors arrived.
7 Couldn't Destroy: Wall Sheena Would Have Prepared Defenders (Attack On Titan)
Bertholdt's success against the outer walls are only for a specific number of circumstances. Paradis had known peace for an entire century up until his attack, thereby rendering them unprepared when he finally arrived to lay waste.
Additionally, the innermost wall would have the highest concentration of defenders. Given that Eren, Levi, and the rest of the Scouts do not have to focus on a broad perimeter and could concentrate their full attention against Bertholdt, he would exhaust himself well before collapsing the final barrier. Without Reiner's assistance, the battle would be severely slanted against him.
6 Could Destroy: Amestris' Alchemists Don't Have The Firepower To Stop Him (Fullmetal Alchemist)
Roy Mustang, Alex Armstrong, and the Elric brothers are the finest state soldiers of the Fullmetal Alchemist universe. However, none of them have displayed enough firepower to take down the Colossal Titan, with most of their attacks able to encompass the side of a building (being charitable).
Ironically, the most qualified people to defeat the Colossal are Scar (who would refuse to save a nation he hates) and Fuhrer King Bradley. However, since the latter cannot regenerate like other homunuculus, he would be repelled by Bertholdt's steam.
5 Couldn't Destroy: The Soul Society's Defenders Are Numerous & Unspeakably Powerful (Bleach)
The Soul Society's many champions are capable of protecting it from Bertholdt's advance. While their natural walls may not be difficult for him to kick down (easily overpowering the gatekeeper, Jidanbo), he would be ripped apart expediently by its captains.
Kenpachi Zaraki and Byakuya specifically have displayed a talent for defeating giants, as proven through their victory against Yammy Llargo (whose unprecedented spiritual pressure poses its own challenge). Therefore, they should have little difficulty destroying Bertholdt before he could wreak further havoc.
4 Could Destroy: None of Cairo's Stand Users Are Decent Counters To The Colossal (JoJo's Bizarre Adventure)
Assuming that DIO's servants are responsible for protecting Cairo if it comes under attack (since it would jeopardize their master), none of them have the potency to bring down the Colossal.
Vanilla Ice and DIO would both be powerless to stop him if he chose to attack at day, D'arby the Player's Stand is ill-equipped to defeat Bertholdt, and Pet Shop could not single-handedly collapse the invader with the force of his Stand.
3 Couldn't Destroy: Liones Is Protected By The Seven Deadly Sins & Other Powerful Knights (Seven Deadly Sins)
Liones does not have as many defenses as other anime cities might. Its standard knights, though gallant, failed to repel the monstrous invasion of the Demon King through their own efforts.
However, the Seven Deadly Sins would prove more than a match for Bertholdt. Merlin could shield them from his initial transformative explosion with her perfect cube and King could petrify him with his Chastiefol. Perhaps most importantly, Escanor could power through the Colossal's steam, obliterating him with a cruel sun (an attack devastating enough to incinerate huge lakes with a single discharge).
2 Could Destroy: Musutafu Isn't Built To Withstand An Invasion (My Hero Academia)
Musutafu was the city that All Might and the other professional heroes defend in the My Hero Academia universe. Despite its many guardians, it is not built for halting invasions, instead purposed for modernized living.
None of Japan's champions would be capable of defeating Bertholdt. All Might has retired, and Edgeshot could not enter his titan on account of the steam it emits. Only Endeavor might pose a threat, though if he was caught in the radius of the initial explosion, he would likely be slain.
1 Couldn't Destroy: Esdeath & The Emperor Are Capable Of Defending The Empire (Akame Ga Kill!)
The Empire was the capital of oppression in Akame Ga Kill!. Between its monarch and General Esdeath, it is extremely well defended. The former is capable of creating unprecedented destruction through the prowess of his Imperial Arms, and the latter took down giants with similar anatomy to Bertholdt's own.
Moreover, Esdeath's ice affinity would allow her a reprieve from Hoover's steam (in a similar regard to how the Scouts doused themselves with water before confronting the smoldering Reiss titan). Using her time-stopping ability to compliment her already formidable defenses, she would be able to defeat the Colossal before succumbing to his flames.