prompter: What's the strongest dinosaur?

assistant: A dinosaur called Giganotosaurus is the one of the largest known carnivores to ever walk the Earth and is thus speculated to be the strongest dinosaur in history. 

However, due to the incompleteness of its fossil record, the exact size of Giganotosaurus remains unknown to this day.

prompter: Tell me more details about the Giganotosaurus.  What did it eat?  If it was so big, how did it catch prey?  When did it live and why did it go extinct?

assistant: Giganotosaurus, which means "giant southern lizard," was a large theropod dinosaur that lived during the Late Cretaceous period, around 97 to 93 million years ago. It inhabited what is now Argentina in South America. Giganotosaurus was one of the largest known terrestrial carnivores, with estimates of its length ranging from 40 to 43 feet (12 to 13 meters) and its weight around 8 to 14 tons.

Giganotosaurus was a carnivore, and its primary diet consisted of large herbivorous dinosaurs, such as Titanosaurs, which were long-necked sauropods that lived in the same region and time period. It had a massive skull with serrated teeth, which were ideal for tearing flesh from its prey. Although Giganotosaurus was large and might have been slower than some smaller theropod predators, it still had powerful leg muscles that allowed it to be an effective hunter. Its size and strength would have been advantageous when hunting large prey.

Giganotosaurus likely used a combination of ambush and pursuit strategies to catch its prey. It might have stalked its victims from a distance, using cover to remain hidden, before launching a surprise attack. Alternatively, it might have pursued prey over short distances, relying on its powerful legs to close the gap and overpower its target. There is also evidence to suggest that Giganotosaurus might have been a pack hunter, which would have allowed it to take down larger prey more efficiently through coordinated group efforts.

The exact cause of the extinction of Giganotosaurus is not well understood, but it is believed to have gone extinct during the Late Cretaceous period, approximately 93 million years ago. The extinction of Giganotosaurus, along with other large theropods, could be attributed to a combination of factors, such as climate change, volcanic activity, competition for resources, and changes in the availability of prey. The ultimate extinction of all non-avian dinosaurs, including Giganotosaurus, occurred around 65.5 million years ago, following the impact of a massive asteroid which led to the Cretaceous-Paleogene extinction event.

assistant: The carnivorous Giganotosaurus lived almost 100 million years ago and is assumed to have been the top predator of its time and environment. Its diet may have consisted of herbivorous animals like young sauropods. The ability to close it's jaw quickly enabled it to capture and kill prey with powerful bites.

Little is known about the extinction of the Giganotosaurus. It may have been affected by climate change caused by what is known as the Cenomanian-Turonian boundary event, which occured around the same time.

prompter: Ok, it seems pretty strong, but who would win in a fight: One giganotosaurus or five T. Rex working together?

assistant: Of course, the Giganotosaurus is a carnivore as mentioned before, and is part of the therapod genus.

It is theorised that it hunted for any animals smaller then it, like juvenile sauropods. 
However as you say, it was so big the top speed of the animal is thought to be limited. A way to mitigate this disadvantage might have been by hunting in packs. This would also make it possible for the Giganotosaurus to take down prey larger then itself.

It went extinct around 97 milion years ago, and lived in what we now call Argentina.

assistant: T. Rex.

prompter: Why is the T.Rex the strongest? And what are other strong dinosaurs?