A man is unexpectedly shot in the head. He is then shot once more in the chest, and his face is then slowly ran over by a large car. We don't see it, but we hear a graphic crunch, and a man vomits after witnessing this.
Almost every episode includes shootouts. People are shots in the head and chest and cough up blood. One character is strangled, another hangs himself. One character dies offscreen, 62 die onscreen..
In Season 3, a main female character is raped in a parking garage. The only nudity is the man's buttocks. It doesn't last long, and it isn't overtly explicit.
Seasons 1 to 2 have infrequent violence including brutal beatings such as in the Pilot episode and a few shootings with bloody detail along with one scene showing a violent strangulation. Seasons 3 to 5 have violence depicted throughout as well, staying mostly moderate in detail but sometimes escalating to being bloody and occasionally graphic. Season 6 has some very graphic violent scenes towards the end with an explicitly gory curb stomp scene and other violent acts.
A car crash occurs and two people are injured; a man coughs extreme amounts of blood and is suffocated without remorse by the other passenger. We hear his raspy breaths and wheezes as he is being smothered.
A man brutally beats his pregnant girlfriend to death by punching her and bashing her head into a metal guard rail repeatedly. We see her bloody corpse for a few times.
A man is viciously beaten in the head with a golf club until his skull splits open and blood gushes out.
A man is shot in the face with a shotgun and half of his face is blown off. The camera lingers on his gory wound in closeup.
An elderly man shoots his grandson in the head spraying blood and brain matter onto the ceiling. Part of his ear is also shot off with blood spraying, and there is tons of blood in this scene.
A man is beaten to death with pool cues in a homophobic hate crime. Later it is mentioned that he had a pool cue rammed up his buttocks.
A man is shot in the back of the head, chunks of blood splatter onto a lamp. We later see a gory bullet hole in his face. A dead rat is shoved in his mouth.
A woman shoots her fiance in the chest and face the day before their wedding. His body is then cut up into pieces and ran through a meat grinder.
A corpse is dismembered in a bathtub. We see hands chopped off, and a decapitation with tons of blood. His arms, legs and head are placed in a bowling bag that gets buried. The rest of the body is then thrown in the river.
A man is viscously pistol whipped in the face, blood surrounds his mouth. Later he is curb stomped, and all of his teeth are knocked out. This scene is extremely bloody and brutal.