Warning: Major spoilers from last night's "Game of Thrones," and potential spoilers for future episodes, are ahead!

On last night's "Game of Thrones," titled "The Mountain and the Viper," one of the season's most exciting plot threads came to a violent end.

Oberyn Martell, the Red Viper of Dorne, came to King's Landing in the first episode of season four to attend Joffrey Baratheon's royal wedding. But he nursed a not-so-secret vendetta against the entire Lannister family for their role in the murder of Oberyn's sister Elia, wife of Rhaegar Targaryen. Specifically, Oberyn wanted justice against Gregor "The Mountain" Clegane, the man who raped Elia, murdered her, and killed her children.

With Tyrion framed for killing King Joffrey, the Red Viper took it upon himself to defend the Imp in trial by combat against a champion of Cersei Lannister's choosing. That champion just so happened to be The Mountain — the man that Oberyn came to King's Landing to kill.

Unfortunately for Oberyn, and just as unfortunately for Tyrion, the Red Viper was not successful, to put it gently. The Mountain crushed Oberyn's head in his hands like an overripe fruit, ending one of the season's best characters with a "sickening crunch."

It was one of the most gruesome scenes "Game of Thrones" has offered up thus far. But how does it compare to Oberyn's death in the books? Let's take a look.

Oberyn enters the picture in the third book in the "A Song of Ice and Fire" series, titled "A Storm of Swords." As on the show, Oberyn serves as one of the three judges during Tyrion's trial. As the trial starts going south, it's Oberyn who approaches Tyrion with the idea of demanding trial by combat, rather than Tyrion making an impulsive, on-the-spot announcement.

On the show, Tyrion is desperate and low in the hours before Oberyn battles the Mountain. In the books, he's a bit more chipper, and even eats an enormous breakfast before the battle begins. Even if Oberyn loses, Tyrion sees the silver lining:

"[If] the Mountain triumphed, Doran Martell might well demand to know why his brother had been served with death instead of the justice Tyrion had promised him. Dorne might crown [Cersei's daughter] Myrcella after all."

When Tyrion meets with Oberyn before the battle, the Red Viper is drinking, just as he is on the show. Tyrion isn't thrilled about Oberyn's beverage of choice, but he's even less thrilled about Oberyn's decision to use a spear against the Mountain. Oberyn is confident, however, as he explains:

"'We are fond of spears in Dorne. Besides, it is the only way to counter his reach. Have a look, Lord Imp, but see you do not touch.' The spear was turned ash eight feet long, the shaft smooth, thick, and heavy. The last two feet of that was steel: a slender leaf-shaped spearhead narrowing to a wicked spike. The edges looked sharp enough to shave with."

Tyrion notices another curious detail about the spear, something that show-only viewers might have missed:

"When Oberyn spun the shaft between the palms of his hands, they glistened black. Oil? Or poison? Tyrion decided that he would sooner not know."

Was the Red Viper's spear laced in poison? And if so, will he have the last laugh against the Mountain, even in death?

On the show, the Red Viper chooses not to use a helmet in battle against the Mountain. In the books, he wears a helmet, but it's barely effective:

"With its visor removed, the prince's helm was effectively no better than a half-helm, lacking even a nasal."

For his part, The Mountain is even more armored up in the books, sporting a massive shield along with his great sword:

"As the Mountain slid his arm through the [shield's] straps, Tyrion saw that the hounds of Clegane had been painted over. This morning Ser Gregor bore the seven-pointed star the Andals had brought to Westeros when they crossed the narrow sea to overwhelm the First Men and their gods. Very pious of you, Cersei, but I doubt the gods will be impressed."

When the battle begins, Oberyn taunts the Mountain with the same Inigo Montoya-inspired speech seen on the show:

"Metal screamed on metal as [Oberyn's] spearhead slid off the Mountain's chest, slicing through the surcoat and leaving a long bright scratch on the steel beneath. 'Elia Martell, Princess of Dorne,' the Red Viper hissed. 'You raped her. You murdered her. You killed her children.'

"Ser Gregor grunted. He made a ponderous charge to hack at the Dornishman's head. Prince Oberyn avoided him easily. 'You raped her. You murdered her. You killed her children.'"

The Mountain is not amused:

"'Did you come to talk or to fight?'

"'I came to hear you confess.'"

On and on the battle goes, with the Viper continuously repeating those words: "You raped her, you murdered her, you killed her children." Eventually, the Mountain gets so frustrated that he charges at Oberyn and swings madly, killing an innocent bystander instead:

"As [the luckless stableboy's] arm rose to protect his face, Gregor's sword took it off between elbow and shoulder. 'Shut UP!' the Mountain howled at the stableboy's scream, and this time he swung the blade sideways, sending the top half of the lad's head across the yard in a spray of blood and brains."

As the fight wears on, the sun breaks "through the low clouds that had hidden the sky since dawn," and Oberyn uses the moment to his advantage:

"Prince Oberyn tilted his dinted metal shield. A shift of sunlight blazed blindingly off polished gold and copper, into the narrow slit of his foe's helm. Clegane lifted his own shield against the glare. Prince Oberyn's spear flashed like lightning and found the gap in the heavy plate, the joint under the arm. The point punched through mail and boiled leather. Gregor gave a choked grunt as the Dornishman twisted his spear and yanked it free."

Blood begins trickling down from the Mountain's armpit, and Tyrion realizes that "he must be bleeding even more heavily inside the breastplate." The Mountain attempts to move forward, but one leg gives out. "Tyrion thought he was going down."

"Prince Oberyn had circled behind him. 'ELIA OF DORNE!' he shouted. Ser Gregor started to turn, but too slow and too late. The spearhead went through the back of the knee this time, through the layers of chain and leather between the plates on thigh and calf. The Mountain reeled, swayed, then collapsed face first on the ground. His huge sword went flying from his hand. Slowly, ponderously, he rolled onto his back."

The Red Viper seizes the opportunity to charge at the Mountain and drive his spear through the massive man's chest, using his whole body weight.

The spear snaps in half as Oberyn drives it through the Mountain, a slight difference from how the spear breaks on the show. All looks lost for the Mountain, so much so that even Tyrion's spirits are lifting:

"'I am feeling more innocent by the instant,' Tyrion told Ellaria Sand beside him."

But the Red Viper isn't satisfied. He wants to hear Gregor confess: "If you die before you say her name, ser, I will hunt you through all seven hells." And unfortunately, Oberyn gets his wish.

"Clegane's hand shot up and grabbed the Dornishman behind the knee. … Gregor's hand tightened and twisted, yanking the Dornishman down on top of him. They wrestled in the dust and blood, the broken spear wobbling back and forth. Tyrion saw with horror that the Mountain had wrapped one huge arm around the prince, drawing him tight against his chest, like a lover."

With that, Clegane makes his confession:

"'Elia of Dorne,' they all heard Ser Gregor say, when they were close enough to kiss. His deep voice boomed within the helm. 'I killed her screaming whelp.' He thrust his free hand into Oberyn's unprotected face, pushing steel fingers into his eyes. 'Then I raped her.' Clegane slammed his fist into the Dornishman's mouth, making splinters of his teeth. 'Then I smashed her f—ing head in. Like this.' As he drew back his huge fist, the blood on his gauntlet seemed to smoke in the cold dawn air. There was a sickening crunch."

There is no explicit mention of Oberyn's head exploding in the chapter, but the "sickening crunch" certainly leaves the visuals up to interpretation.

On seeing the Red Viper's demise, Ellaria Sand screams in horror, and Tyrion throws up his glorious breakfast. Moments later, as he's escorted back to his prison cell, he breaks down with something of an Arya Stark moment:

"I put my life in the Red Viper's hands, and he dropped it. When he remembered, too late, that snakes had no hands, Tyrion began to laugh hysterically."

Do you prefer the show or the book's version of Oberyn's death?