Batman and The Red Hood have a long and intense fight.
Multiple onscreen shootings, burnings, and murders. Quite a lot of blood is shown. Lots of hand to hand combat as would be normally expected in a Batman movie.
There's lots of bloody bits in this.
Joker beats Robin with a crowbar. It is VERY brutal and blood is shown.
Black Mask punches his new gang member. A bleeding nose is showing. Black Mask also proceeds to punch several of his own men throughout the movie.
Red Hood throws a bag onto a table containing several decapitated heads of crime lords.
Red Hood shocks a guy and kills him by overloading his cybernetic helmet to backfire on him. Blood is shown splattering on the wall. The most graphic bit in the movie.
Red Hood beats Joker with a crowbar as a form of revenge when for kidnapping him and brutally torturing him.
Batman throws a batarang and blows up the gun Red Hood had and blood is on his hand.
A Molotov cocktail is shown detonating in someone's hand before they threw it, and is strongly implied to have burned the man to death.
The Joker managed to slit a man's throat with a glass of water, as well as kill four armed men with a stolen pistol while being recruited by Black Mask.
The Joker briefly sprays kerosene onto his hostages before dumping the gas tank into the truck, and eventually drops a lit lighter on them with the obvious intention of torching them.