Nephthys
The Gr8est!!!!!!!!
The Third Lesson:
"At 10 meters, Malgus extended his free hand and loosed veins of blue Force Lightning. They struck the charging Jedi, swept through his defenses, swirled around him and began to burn flesh.
Shouting with pain, the Jedi leaned forward into the lightning - teeth bare, blue blades held before him - and staggered toward Malgus. Despite his burns, he came onward. One step, another, another, but he was failing, wilting in the heat of the lightning. Malgus channeled more power and the Jedi fell to his knees, screaming. The lightning spiraled around the Zabrak, blasting dark holes in his body. The lightsabers fell from his hands and he writhged in agony, screaming his pain to the sky."
As mentioned, this is the same Jedi who collapsed two buildings on Malgus and Malgus was grievously wounded (as in, afterwards he needed cybernetics installed to survive) at the time. The guy also had two lightsabers, which I believe makes it easier to block lightning and Malgus overpowers him easily. The text notes that Malgus could kill him at any time and he's extremely casual in his attack until he amps up the power. Lastly note that he blasts holes in the Jedi's body with his lightning, an extremely impressive display (whats more impressive is that the Jedi actually survives that. The guys a fvcking badass).
All from Deceived:
"Malgus, not to be outdone, picked a Jedi Knight at random, a human female ten meters away, held forth his left hand, and discharged veins of blue lightning from his fingertips. The jagged lines of energy cut a swath through the battle, harvesting two Padawans as they went, until they caught up to the Jedi Knight and lifted her off her feet.
She screamed as the lightning ripped into her, her flesh made temporarily translucent from the dark power coursing through her. Malgus savored her pain as she died."
"As Aryn prepared to leap at Malgus, he held forth a hand, almost casually, and lightning sizzled through the space between them. Aryn interposed her lightsabers, but the power in the lightning exceeded anything she had felt from Malgus before. It blasted through her defenses and both lightsabers flew from her hands. The lightning seized her, lifted her up, and threw her from the top of the shuttle."
Bare in mind that Aryn had earlier been able to block Malgus' lightning with a single lightsaber in midair, which speaks of the boost Malgus received when he embraced the darkside.
Also he actually did it 3 times:
"Malgus held forth his hand and the rage within him manifested in blue veins of lightning that discharged from his fingertips and slammed into Adraas. The power stopped Adraas’s charge cold, blew his lightsaber from his hand, caught him up in a cage of burning lightning. He screamed, squirming in frustration and pain."
YouTube video
1.10 Note that the Strike Team Malgus blasted either contained the HoT and the Barsen'thor or Darth Nox and the Emperor's Wrath.