Elijah bargaining the cure for a werewolf bite for Jane-Anne's body.
Earlier in the same episode, Elijah's heart-to-heart with his little brother, Klaus. The speech he gave plus the beat-down was quite the awesome combo. Even if Klaus was beating him up, too. It's these scenes that make Klaus daggering his brother again all the more heartwrenching.
In the episode "House of the Rising Son", Davina throws an Original Vampire out the window with only her mind.
But not before knocking out Rebekah, said Original Vampire, and erasing her memory of the location of the Church she was in.
Later on, she then boils Klaus' blood from the inside. The only reason Klaus made it out of the church alive was because he had the foresight to bring a hostage with him: Davina's childhood friend Tim.
Klaus pulls a truly masterful Batman Gambit in the third episode, manipulating basically the entire rest of the cast to his own ends. It ends poorly for everyone but Klaus, naturally.
Marcel's Big Damn Heroes moment, where he swooped in to stop the Harvest Ritual Sowing and saved Davina's life.
Elijah, killing Agnes. "No one hurts my family. No one."
Even though Marcel's plans against Klaus has failed and he lost his kingdom towards him he manages to have one final moment of defiance by giving Klaus "The Reason You Suck" Speech by explaining how meaningless Klaus's victory is.
Which speaks volumes given how Klaus has pretty much drove his family away, caused Hayley to hate him, and even destroyed any chance at being a father to his unborn child.
Before the above, Klaus versus something on the order of fifty to a hundred vampires at once. He just lets them beat on him for a while, and it actually looks like they might have a chance, Rebekah even stepping forward as if she's about to add a few hits herself. And then Klaus looks up, his eyes go yellow and the veins appear, and he growls deep in his throat. And proceeds to completely annihilate everybody in his path until Marcel surrenders. Rebekah's look of horror is what ultimately sells it. Counting up the casualties, approximately two dozen vampires were permanently killed in that fight.
In a subsequent episode, Elijah stops a vampire hunting party out to kill werewolves by very calmly pointing out that there were considerably more of them when they tangled with his little brother Niklaus. The vampires back down immediately.
Davina using her telekinesis to simultaneously break four witches necks at the same time.
Davina: ( Dismissively) That's enough out of you. Then snaps his neck with a gesture
She didn't just make Klaus beg in front of her. She was about to force him to turn into a werewolf. This is only topped off by her making Elijah choke on a thousand years' of blood. And before Rebekah appears to save him, she was going to boil Marcel in bronze.
Klaus backup plan was a dark one, reminding everyone why he is MagnificentBastard that is more then brute strength.
Even Marcel has a backup plan just in case Klaus enacts his, in effect saving Davina from a lethal poison not even Vampire Blood could heal. Then again he had a hell of a teacher..
Celeste has been playing a long game since before the series started, and by episode 13, the fruits of her labour sees Sophie-Anne dead, Klaus and Rebekah MIA, Hayley almost killed and Elijah severely emotionally compromised by her reappearance and the subsequent fall-out on his family.
It soon becomes clear that Celeste's plan is not just revenge. She wants to tear the bond between the Mikaelsons asunder, and so far she seems to be succeeding.
Hayley knocking out Celeste and capturing her was pretty awesome, considering the trouble Celeste made for the Originals.
Rebekah - weak with werewolf venom, delirious and scared out of her mind - is cornered by a vengeful Klaus after he learns that she and Marcel had summoned their father Mikael to New Orleans to kill him. And what does she do? She picks up a rusty iron and charges at him. It isn't effective, but Rebekah will be damned before she goes down fighting.
Elijah's Big Damn Heroes moment, when he stabs Klaus with Papa Tunde's knife before he can do the same to Rebekah. Subverted in that this action might have come at the cost of whatever trust Klaus still had in his big brother.
In his mission to resurrect Davina, Marcel gets one when he takes out an Elder Witch using surprise tactics, and rips off her head one handed...
In the flashback of 1.15, we have Elijah standing up to Mikael and calling him 'a fool without equal' for even thinking that he would kill his own brother. Considering that Mikael has the in-universe nickname of The Destroyer, that took serious balls.
Cami deserves a mention for not only staying with Klaus - when there was a good chance she would be the victim of his fury - but she tries to get him to stop going off to kill Rebekah with his white oak stake.
Elijah outsmarting Celeste by enlisting Monique's help to seal her spirit back in her original body after she 'kills' herself, thereby cutting her off from her source of immortality.