The pre-rendered introduction cinematic before reaching the main menu is a retelling of Wiedźmin, published way back in 1991, and it's an excellent, action-packed sequence, staying almost entirely true to the original story, down to each individual blow. A breakdown on this fantastic intro to this mythos.
Geralt prepping all his tools of the trade as the sun sets on the old manor along with an awesome voice over narration.
A key game mechanic, but the detailed visuals of the potion imbibement definitely count. Geralt seems to take an infusion of Cat, Petri's Philter and an unknown third toxin to increase sensory perception and for a moment our protagonist looks as evil as the stories the old wives would have their children believe. The poisons course through his veins and turn them black, his facial bones shift under his skin, becoming gaunt and bestial and his gold eyes blaze even brighter than before. A clear indication that our hero isn't remotely human.
The fact that Geralt can hear the Foltest family crypt inch open from his position across the courtyard and up from the deep catacombs.
Using the traitor responsible for Adda's curse, Ostrit. (Who tried to bribe, then threaten, Geralt to leave,) as bait to lure the monstrous Princess right where he wants her.
Geralt's use of Le Parkour to navigate the crumbling battlements and how he can passively fight a barrel-chested, incredibly powerful young monster by repeatedly diverting her clawed swipes and knocking her back with hand-to-hand combat.
Silver chain Weapon Twirling, plus catching Adda with it while she's in a mid-air leap.
Striga!Adda gets one too when she busts free of a material which is supposed to be as kryptonite to Necrophages.
Geralt using both the Quen and Aard Signs in tandem to unleash a Charge Attack that is literally a torrent storm of Hex power crackling from the monster hunter's hands. Also, the smirk he gives when it tears Adda off her four paws for the second time when she manages to crawl up to him; roaring, just inches away from the source.
After punishing her with an interesting variant of the "Hey, You!" Haymaker. The silver sword finally comes out. But at this point, all Geralt has to do is an Intimidation Demonstration coupled with a bit of a Close Callhaircut that exemplifies his masterful control and the traumatized girl of a monster runs for the hills.
The Witcher takes what could be White Honey to detoxify his souped up enzymes, seals himself in Adda's coffin for the rest of the night with a Yrden and promptly falls asleep while she futilely bashes on the stone lid from the other side!
the next morning. With the curse apparently lifted. Geralt somehow survives having his throat torn out by Adda's partially cursed arm and still partially rabid mind. Fridge Horror sets in when you see he has no reminders of the wounds on his neck in-game, imagine how grisly his other collection of injuries, seen all over his torso, arms and legs in the second installment, not to mention his facial scars in the first, must have been to leave marks when being "gravely wounded" turns out to be an eventual full recovery...
In the first major quest hub, if you chose to save the witch that's being hunted by the villagers of the Outskirts, Geralt delivers an awesome rebuke towards the torch and pitch-fork wielding mob and their crazed fanatic of a ring-leader. Did I mention he stops said instigator cold by holding him at blade-point?
The Reverend: Begone, Witcher! And leave the witch, or we'll burn you too!
Geralt: I'd like to see you try, pleb. (places steel sword tip under his beard)
The Reverend: Uuuuuh!
Geralt: Shove off. And maybe I'll let you be... You have two options. Wait until I leave and then murder Abigail - but then I'll come back. I'll slay every lice ridden peasant, anything that moves and can't climb a tree. Or, you can lead honorable lives, clear your conscience, start again - like humans. The choice is yours.
The fight with the Tower Golem in a raging thunderstorm.
Then clobbering Javed with your spiked glove after you solve the massive Salamandra case in Chapter II, and find out he's posing as Raymond with a magical illusion. Then you get to take on both him and the Professor within a burning circle of fire, sometimes at night and nearly always in the pouring rain. Epic.
Geralt manages to get the best of both of them in regards to fencing. So the prof is forced to use an alchemical gas bomb to bring Geralt to his knees, then the pair of them flee through a teleportation portal before he recovers!
Vincent Meis, Captain of the Guard by day, lycanthrope batman of the Temerian Capital by night. When Geralt stumbles upon his lair, stocked with weapons and armour, he actually quips whether Vince thinks himself a superhero!
And if you spare him. He'll aid you later in the game against Salamandra thugs, whether he's cured or not.
When Geralt storms Salamandra's main lab in the Trade Quarter with his allies and cuts down the Professor, we get this awesome Call Back to when the infamous bandit shot poor Leo with a crossbow.
Professor: You have what you came for... Show mercy. (fires hidden wrist crossbow)
Geralt:(deflects quarrel with disdain)
Professor: So it's true. Witcher's can parry bolts in flight!
After escaping the turmoil in Vizima, Geralt resolves a conflict between a group of sentient amphibians called the Vodyanoi and the human settlement of Murky Waters. For his actions, the Lady goddess of the Lake knights Geralt, gives him a magic sword, and tells him to go and face his destiny. That's right, Geralt is now King Arthur.
Actually, the sword in question Geralt receives is a silver blade called Aerondight. "Arondight" was the sword given by the Lady to a very different, somewhat philandering knight, effectively turning Geralt into Lancelot. Which is actually even more appropriate!
Geralt vs the Assassin in the closing cinematic.
Foltest gets one for being able to last more than a second unarmed against a mutant.
Another for the White Wolf, the rival Witcher seems to be doped up to the gills on Blizzard and Willow, making both Geralt's enhanced reflexes and his magic all but useless. Our hero is on the ropes, but, being a consummate professional, Geralt off-sets the assassin's guard by throwing his hefty reward pouch in his face, bursting coins out everywhere, lops of his right arm, cuts his belly open and lays open his spine; all before every last Gold Crown showers to the floor.