A "super-breed" dog was found licking blood calmly after killing a man in a Hampshire park, an inquest heard.
Ian Symes, 34, was walking an American Bully XL when the animal, named Kong, overpowered him and mauled him to death.
The dog had been bought by Mr Symes' friend Callum Jones the previous day over Snapchat from travellers - and there was no paperwork.
At the inquest, Mr Jones said the dog was bigger than he expected when he bought it.
He explained: "He looked smaller in the pictures, I was quite surprised by how big he was.
"He did pull quite a lot, I did struggle to walk him, I was a bit worried about that.
"I took him out with my neighbour once [the evening before Mr Symes' death], the whole way he was just pulling so we decided to go back, there was no way I was walking him as he was so strong.
"I did warn [Mr Symes and Mr Keltie] not to walk him. I said you can't have one person take him out."
Mr Jones said he was walking back from his partner's home at 10.20am on August 10 when he discovered his dog and fatally-wounded Mr Symes at Fareham Park Recreation Ground, with the dog licking blood.
He said: "Kong was licking blood and that's when I started freaking out and shouted for help... the dog was so calm and licking him, he didn't seem in an aggressive manner."
Paul Keltie, who was looking after the dog with Mr Symes, said Kong appeared "friendly" and despite being "very strong", he looked "gentle".
Local Stacey Marsh said she saw Mr Symes playing with the dog in a "boisterous" way by tapping his cheeks, later telling the animal "that's enough now".
Julieann Abbott, whose home backs onto the field, said she heard "gurgling" noises 10 minutes before hearing Mr Jones screaming for help.
The Bully XL - which shares DNA with banned American Pit Bull Terriers - reverted to its "aggressive" natural instincts and repeatedly bit down on Mr Symes' neck after he began playing with it, Portsmouth Coroners' Court heard.
The dog, which had not been "socialised", punctured the man's jugular vein, "crushed his voice box", caused "widespread mangling", and "ragged" him around on the ground.
During the inquest, animal expert Dr Candy d'Sa, who assessed Kong after the attack, gave a stark warning about the Bully XL breed which she said has been "genetically modified" from banned Pit Bulls.
Dr d'Sa said of the 10 Brits killed by dogs in 2022, five were mauled by the new "super-breed" which has only existed for around 15 years and is "bigger and stronger" than their prohibited relatives.
Dr d'Sa said she believes Mr Symes, one of the five to have been killed in 2022, died when "rough play" with Kong quickly turned into "predatory behaviour" and its "prey drive" kicked in.
Dr Basil Purdue, a Home Office pathologist who carried out the post-mortem, said: "The cause of death was clearly the result of overwhelming neck injuries in keeping with infliction by a large, powerful dog.
"It is notable that the dog he was walking weighed slightly more than he did and was powerful in stature."
