Some of these pictures and descriptions give away plot details that you might not want to know before watching the film.
The two Kill Bill movies directed by Quentin Tarantino combine to be one long Kung-fu Samarai Anime Spaghetti Western revenge story with a very cool snake scene. The story revolves around the members of the Deadly Viper Assassination Squad led by a man named Bill. They travel around the world killing people for money. Each member has the codename of a snake: Bill is Snake Charmer, Elle Driver is California Mountain Snake, O-Ren Ishii is Cottonmouth, Vernita Green is Copperhead, Budd is Sidewinder, and since she's the deadliest assassin, Beatrix Kiddo is named after the deadliest snake: Black Mamba. (The black mamba is probably not the deadliest snake in the world. Other snakes have more potent venom or kill more people each year, but the mamba is definitely in the top ten and can kill you very dead just the same.) All of the snake codenames for the squad are the common names of real venomous snakes except California Mountain Snake (which is probably meant to refer to the California Mountain Kingsnake, which is not a venomous species) but only the Sidewinder and the Cottonmouth are actually Vipers.
In Kill Bill Vol. 1, Bill crashes the wedding rehearsal of the very pregnant Black Mamba (Uma Thurman) who abandoned Bill with his baby to work at a used record store in El Paso. (Without explanation, the movie is very squirly about her name. We know her only by her codename Black Mamba and by her new alias, Arlene Plimpton, and she is also referred to as "The Bride." Any time someone says her real name, the sound is censored with a beep. We never hear her real name until about half way through the second movie.) Bill uses all four members of the Deadly Viper Assassination Squad to kill the groom, the preacher and his wife, the organ player, and everyone else in the church . Then Bill shoots the wounded pregnant Black Mamba in the head and leaves her for dead. At this point we all want to kill Bill. The press calls it "the El Paso Wedding Chapel Massacre."
Miraculously, The Bride survives. She spends four years in a hospital coma, waking suddenly with a metal plate in her head and an urgent need to set out on a "roaring rampage of revenge" to kill all five Deadly Viper Assassination Squad members, one at a time. She even makes a list. Then she goes to Okinawa where a legendary sword-maker creates the deadliest Samurai sword he's ever made for her, and then she starts crossing names off her list. (She only ends up killing one of the five with the sword, but she makes up for that by using it to fight a small army of bodyguards in Tokyo.)
In Kill Bill Vol. 2, Black Mamba, eventually known also as Beatrix Kiddo, moves on to the third member of the Deadly Viper Assassination Squad on her list: Budd (Michael Madsen) codename Sidewinder. (She doesn't know she will also find member number four there: Elle Driver, codename California Mountain Snake.) Beatrix finds Budd living in a run-down isolated trailer in the Mojave Desert, a broke drunk working as a bouncer at a topless bar. (That's my dream life!) He knows she's coming, and he's waiting for her. He shoots two barrels of rock salt into her chest, injects a sedative into her butt, ties her up, nails her inside a coffin, and buries her alive in a cemetary in someone else's grave. (Budd later calls that a "Texas funeral.") He calls Elle and tells her that he'll sell her Beatrix' priceless Samurai sword for a million dollars in cash, and Elle agrees.
The Snake Scene
The next morning Elle drives to Budd's trailer and hands him a bright red suitcase full of bundled one hundred-dollar bills. Budd smiles and greedily begins pulling out stacks of bills until he sees a black mamba that was hiding under the money. The snake rears up and hisses then strikes Budd's face over and over again, in a fast-paced snake attack montage that is accompanied by Tarantino's trademark exaggerated unnatural sound effects with whips cracking, explosive hissing and crashing and crunching sounds, along with Budd's screams. Budd reacts as if he's being beaten with a baseball bat, thrashing around, tearing up the place, knocking the suitcase off the table, and finally collapsing onto the floor where we see his face covered with huge red bite marks.
The real black mamba has small fangs and only needs to bite once, but all movie snakes have two huge fangs and strike repeatedly - that's the stupid convention for movie snake attacks. Tarantino knows this rule, and enjoys playing with it, making this one of the few snake attack scenes where all the unnatural exaggeration actually makes the scene more powerful and more entertaining. (Sure, it's unbelievable to think a snake could be used as a weapon in this way, with so many ways it could have gone wrong. Sometimes you just have to suspend your disbelief. My disbelief was suspended a lot in these movies.)
As Budd lies on the floor dying, Elle lights a cigarette and sarcastically apologizes, telling Budd that it was rude of her not to introduce him to her friend the black mamba, as the snake crawls away. Then she pulls out a long list of facts about black mambas that she found on the internet and wrote by hand in a small tablet. She reads all of it slowly to Budd, because, as she tells us, it takes about 20 minutes for the venom to kill a person bitten repeatedly on the face:
"In Africa, the saying goes, in the bush, an elephant can kill you, a leopard can kill you, and a black mamba can kill you. But only with the mamba, and this has been true in Africa since the dawn of time, is death sure. Hence, it's handle: Death Incarnate. Pretty cool huh? Its neurotoxic venom is one of nature's most effective poisons, acting on the nervous system causing paralysis. The venom of a black mamba can kill a human being in 4 hours, if say, bitten on the ankle or the thumb, however, a bite to the face or torso can bring death from paralysis within 20 minutes. … The amount of venom that can be delivered from a single bite can be gargantuan. … If not treated quickly with anti-venom 10-15 mg can be fatal to human beings. However, the black mamba can deliver as much as 100 to 400 mg of venom from a single bite."
When Bill calls Elle she lies to him, telling him that Beatrix killed Budd by putting her namesake black mamba in his camper. As Elle leaves the trailer with the sword and the cash, Beatrix, who has punched her way out of the coffin, dug her way out of six feet of dirt, and walked all the way back to Budd's trailer, viciously attacks her starting what Tarantino called the "war of the blonde gargatuans - two Amazon chicks beating the hell out of each other." After a fierce fight in the cramped trailer, Beatrix rips Elle's remaining eye out of her head and ends the fight, with Elle flailing around in the trailer like the dying Pris in Blade Runner. We see the black mamba one last time as it rears up and hisses when Beatrix walks past it barefoot. Maybe the snake then bites and kills Elle, but we don't know for sure if she's alive or dead. (The end credits show four of the actors who played members of the Deadly Viper Assassination Squad and died with their names crossed out, but there is a question mark over Daryl Hannah's name.)
I can't imagine Tarantino turning down the chance to use a real black mamba in a movie, so my guess is that they used close-ups of a juvenile black mamba that were filmed off the set in a controlled situation. The inside of the mouth of the snake we see appears to be black, which is what gives the mamba its name. (Although they could have died it black.) They also used a similar-looking but different, likely non-venomous species for some of the longer shots (including the first shot we see of the snake lying on top of stacks of bills, before it strikes Budd.)
The snake hanging off Budd's face is obviously a fake snake prop, and not a very convincing one, because unfortunately, hanging a live black mamba by its venom-dripping fangs from an actor's forehead is against the rules. I'm sure Michael Madsen would have done it. He's no wimp. (I am totally kidding! Nobody on a film set should be allowed anywhere near a dangerous venomous snake except for experienced snake wranglers.)
It's been said that the black mamba attack here was borrowed from the movie Venom, in which a woman opens a box holding a black mamba that strikes her in the face. That could be, and there's also a similar explanation of facts about black mambas in Venom, but it's really just a variation on the idea of making a booby trap by putting a rattlesnake in a mailbox. Kill Bill nicely expands on the idea by letting the mamba get exposed through Budd's greed in wanting to touch the money - it's not just an accidental encounter - and by letting Elle blame Beatrix for the murder by using the species of snake that is her codename.
After watching this, I vowed to never open a suitcase packed with a million dollars in cash without first checking for snakes. So far I have kept my vow. Feel free to tempt me to break it.