Respect Vergere:

Dark Rage/Protection/Speed

Dark Rage is a dark-sided power enabling a Jedi to enhance one's resolve and physical traits. Force Protection is the passive (and sometimes active) enhancement of a Force sensitive's durability to varying superhuman degrees. Force Speed is the passive (and sometimes active) enhancement of a Force sensitive's speed to varying superhuman degrees.

Vergere reacts to Force Lightning, deflecting it on her blade:

Jaina sneered at the creature, then raised her hand and loosed another bolt of Force lightning.

Anakin's lightsaber snapped to life in Vergere's hand and rose to intercept the attack. Then, eyes going wide, she turned and fled into the warren, the lit blade wagging behind her like a tail.

Source: The New Jedi Order: Star by Star

Vergere jumps to avoid blaster fire:

Four blaster bolts lanced down into the mortuary pit, but Zekk's hand crashed down across Jaina's barrel and her shot went wide, burning into the ground next to Vergere's feet. The creature was already jumping to one side, Anakin's lightsaber coming around smoothly, as though she actually knew how to use it - a notion that was dispelled when she let it slip from her hand and clatter bladeless to the ground.

Source: The New Jedi Order: Star by Star

Sever Force

Sever Force is a Force Power enabling one to cut another Force user off from the Force.

Vergere uses Sever Force on Jacen Solo:

"There are no Jedi here," she said, and made a gesture, eyeflick-swift. Inside Jacen's head, a swirl of interstellar gases fell in upon itself, kindling a protostar behind his eyes. The protostar swelled, gathering power, ramping up intensity until the light inside his skull washed away the woody glow of the chamber in which he hung. In the whited-out blaze, he heard Vergere's voice, cold and precise as the light of a distant quasar.

"I am your guide through the lands of the dead."

Beyond that, he heard and saw no more. A silent supernova erupted within Jacen's brain, and blasted away the universe. Seconds or centuries passed in oblivion. Consciousness swam back into him, and he opened his eyes to find himself still hanging in the Embrace of Pain, Vergere still standing below him, on her face the same alien facsimile of cheerful mockery.

Nothing had changed. Everything had changed. The universe was empty, now.

"What?..." Jacen croaked, his throat raw as though he'd spent days screaming in his sleep. "What have you done to me?..."

"You have no business with the Force, nor it with you. Let you have the Force? The idea!

It must be some kind of human thing... you mammals are so impulsive, so reckless: infants teething on a blaster. No, no, no, little Solo. The Force is much too dangerous for children.

A great deal more dangerous than those ridiculous lightsabers you all seem to like to wave about. So I took it away from you."

The emptiness of the universe howled inside his head. There was nothing out there. Only vast interstellar vacuum. All his training, all his talent, his gift, meant nothing to the limitlessly indifferent cosmos; the Force was only the ghost of a dream from which he had now awakened. Jaina... He thrust desperately into the bond that had always been there, seeking his sister, his twin; he poured his terror and loss into the void that yawned where that bond had always been.

Only silence. Only emptiness. Only lack.

Oh, Jaina Jaina, I'm sorry... With the Force-bond between them shattered, even Jaina would think he was dead. Would know he was dead.

"You.... there's no way.... you can't possibly..."

He barely recognized this tiny, lost-in-the-dark whisper as his own voice.

"But I have. Really, this Force business, you're better off without it. If you're a good boy, I'll give it back when you grow up."

...

Jacen Solo was once more swallowed by agony. Now there is no more Force for Jacen--no more cool breath of life and sanity, no more Jaina, no more life. Where Jacen is, there is only the white.

Source: The New Jedi Order: Traitor

Force Concealment

Force Concealment is a Force power enabling a Force user to mask their presence or alignment in the Force.

Vergere vanishes from Luke's Force senses, preventing him from detecting her through the Force despite him being able to clearly see her sitting across from him:

But what Luke could not detect was Vergere. She seemed to have vanished completely from his Force-awareness, even though he could plainly see her sitting on her stool across from him.

Source: The New Jedi Order: Destiny's Way

Mara Jade and Luke discuss how they cannot Sense anything about Vergere, except what she wants to be Sensed. As thus, she is practically invisible:

"She doesn't feel anything. She's practically invisible. We only sense what she wants us to sense."

Source: The New Jedi Order: Destiny's Way

Art of the Small

Art of the Small is an extremely esoteric Force power enabling a Force user to shrink their presence in the Force to microscopic sizes, allowing them to influence things on a molecular scale.

Vergere reveals that she can shrink her mind and Force-awareness so that her opponents cannot sense her much in the same way as they cannot find one molecule amidst billions of others. She reveals that in this way, she can rearrange molecules, taking them apart or building new ones:

"I call it making myself small. I narrow my focus bit by bit until it becomes, well, microscopic. Tiny. My mind and Force-awareness I shrank to an infinitesimal size. An enemy has the same chance of finding me as his chance of finding one molecule amid billions of others."

"Your tears," Luke said. "That's how you make your tears."

"Very good, young Master," Vergere said. "Yes. In that state I can rearrange molecules, take them apart, and build new ones bit by bit. I use my tears because they are convenient, but I can accomplish the same thing with other material."

"I know a Jedi healer, Cilghal, who would delight in this technique."

"I'll try to teach her, if you and she are willing. If I'm ever permitted to leave this place."

"You can teach without leaving this room," Luke reminded her.

A sly smile drifted across Vergere's face. "I can-but will I?"

Vergere gave one of her wheezing laughs, and popped a candy into her wide mouth.

Source: The New Jedi Order: Destiny's Way

As Vergere revealed, she could utilize Art of the Small to give her tears healing properties. She used these tears to save Mara Jade Skywalker's life:

Vergere had been involved in one of the Yuuzhan Vong's first efforts to assassinate the Jedi, but she had also been the one who had given their father the healing tears that had first put Mara's illness into remission. To this day, there remained disagreement over whether Vergere was a friend or foe of the Jedi, a mere pet of the assassin or an agent in her own right.

Source: The New Jedi Order: Star by Star

Force Ghost

Vergere appears as a Force Ghost to Jacen after her death:

"You chose with your heart. And you achieved your object, did you not? Your sister lives." She looked at him solemnly. "And I achieved my object as well. You are free to pursue your destiny."

Truth struck Jacen. He looked at Vergere in shock.

"I just realized," he said. "You're dead, aren't you?"

Source: The New Jedi Order: Destiny's Way