The 56-year-old, who was working locally, lost a substantial part of his ear after he was woken up by Philip McGilvray, 33, and Alan French, 32, shouting in the corridor outside his room.
The jury heard having twice asked the pair to keep quiet, he tried to force his way through them to get to the Newcastle Quayside Travelodge reception to complain when they laid into him.
Mr Mantle described to the court the "melee" that ensued and that among the many punches thrown, the pair landed "four absolute pearlers".
He also said having pinned him to the floor he received three bites to his ear.
"I remember being attacked by two men with every blow they had in their armoury," he said.
"It was like two hyenas bringing down an old water buffalo. I had one person on each arm.
"I was trying to get rid of them and I was trying to run away. I was completely hamstrung by that."
But Robin Patton, defending Mr McGilvray, accused the actor of losing his temper and running at the two men.
He said Mr Mantle knocked Mr McGilvray to the ground and ended up on top of him.
"I suggest that you had lost your temper and gone back into your room a bit cross, the noise continues and you go out again and you run at them," he said.
"You took out Philip McGilvray, he did not stand a chance and with your weight you took him to the ground."
But in response to the accusations, the actor replied "absolutely not" and said he was "flabbergasted" at Mr Patton's assertions.
Yesterday Mr Mantle told Newcastle Crown Court that Alice Klenk, his "guardian angel" and a nurse staying at the hotel with her partner, heard the fighting and came out of her room.
She grabbed both defendants by the scruff of the neck to stop them having another go at Mr Mantle, the jury heard.
The actor, who has also appeared in Game of Thrones, said: "She literally saved me from a lot further damage."
After staggering to his feet, he saw there was blood all over him.
"I looked down on the floor and there was my ear lying on the carpet," he said.
"That brings things into focus."
He picked it up with one hand and grabbed one of the men with the other, he said.
"I had my ear in my left hand, I got back to my room and she put it in a glass of water to preserve it, so they would be able to re-attach it.
McGilvray and French, both 32, and from Hamilton, Scotland, deny wounding with intent.
The court had been told there was no dispute about what McGilvray did and French was charged with the same offence because he was jointly responsible, Jolyon Perks, prosecuting, said.
The trial continues.