Asriel stronger than humans?

A small question. During the Undertale Pacifist and Neutral routes, the monsters narrate the Story of Asriel and Chara. They say that Asriel became a being of incredible power when he absorbed the SOUL of Chara. It was okay till then.

But, when the humans started hitting him for their allegations of killing Chara, they said that Asriel could kill all those humans. How is this possible? Is a human and monster SOUL together far stronger than many Human SOULS fighting together?

We call Asriel the God of Hyperdeath because it is impossible for one Human Frisk to defeat a being with the power of 7 Human souls. But if Asriel were to fight with entire humanity... I don't think he stands a chance... does he? Moreover, Asriel has absorbed every SOUL of the underground so he has no one to fight by his side and all alone. Asriel can't win the battle against Humanity... can he?