Like a hell-broth boil and bubble
The Dark One, representing the evil side of everything, including witchcraft, tries to disrupt the Pattern with what have been described as ‘bubbles of evil’ that warp reality.
At first, his touch being weak, the Dark One sensibly aimed the bubbles squarely at the three ta’veren – their very ta’veren-ness probably making this process easier. The very first bubble hit Rand:
The wind howled across the tower . . . and trapped him. It was as if the air had suddenly jelled, holding him in a cocoon. Pushing him forward. Time and motion slowed; horrified, he watched Lan's practice sword drift toward his chest. There was nothing slow or soft about the impact. His ribs creaked as if he had been struck with a hammer. He grunted, but the wind would not allow him to give way; it still carried him forward, instead.While Borderlanders such as Lan are used to their lands being close enough to the sealed Bore to be affected by the Dark One’s influence, this was a strange enough occurrence to trouble Lan. And it takes something significant to trouble Lan.
The lathes of Lan's practice sword flexed and bent - ever so slowly, it seemed to Rand - then shattered, sharp points oozing toward his heart, jagged lathes piercing his skin. Pain lanced through his body; his whole skin felt slashed. He burned as though the sun had flared to crisp him like bacon in a pan.
With a shout, he threw himself stumbling back, falling against the stone wall. Hand trembling, he touched the gashes on his chest and raised bloody fingers before his gray eyes in disbelief.
"And what was that fool move, sheepherder?" Lan grated. "You know better by now, or should unless you have forgotten everything I've tried to teach you. How badly are you - ?" He cut off as Rand looked up at him.
"The wind." Rand's mouth was dry. "It - it pushed me! It . . . It was solid as a wall!"
The Warder stared at him in silence, then offered a hand. Rand took it and let himself be pulled to his feet.
"Strange things can happen this close to the Blight," Lan said finally, but for all the flatness of the words he sounded troubled. That in itself was strange.
The Great Hunt, The Flame of Tar Valon
It was not until the second bubble spectacularly burst in Tear in The Shadow Rising, that their nature became more obvious. All three ta’veren were affected simultaneously, and with witnesses present.
A cock crows in the middle of the night – a sign of a false dawn, and believed by all to be an omen that someone is going to die - and, as the chapter title says, a whirlpool forms in the Pattern.
Perrin was attacked by his axe. Its murderous fury goes when Perrin 'disarms' his axe by burying it in the door.
Earlier, Mat the trickster is tricked by Rhuarc into asking the Maidens how to play Maiden's Kiss. The gamester was outplayed for once. In an Alice in Wonderland scene, the rulers on Mat’s playing cards come to life. How appropriate that Mat, who fears the One Power so, is attacked first by the Amyrlin card. Mat knifes the three animated cards to stop their attack.
Rand is attacked by images of himself. They step out of mirrors and polished silver; anything that reflects. The three reflections don't cooperate, each wants to take over Rand's body for itself, a sure sign the Shadow is involved, or that the reflections bear the essence of the Shadow, since the Shadow is always uncooperative. One tries to suck Rand’s life force, but he absorbs it and then draws up the life of his remaining reflections.
Moiraine suggests the attack was caused by evil leaking from the Dark One's prison as the Seals weaken:
“Not one of the Forsaken,” Moiraine cut in. “I think not. This was too simple. And too complex.”It is indeed a time for reflection.
Rand spoke calmly. “No riddles, Moiraine. If not the Forsaken, who? Or what?”
The Aes Sedai’s face could have done for an anvil, yet she hesitated, feeling her way. There was no telling whether she was unsure of the answer or deciding how much to reveal.
“As the seals holding the Dark One’s prison weaken,” she said after a time, “it may be inevitable that a ... miasma ... will escape even while he is still held. Like bubbles rising from the things rotting on the bottom of a pond. But these bubbles will drift through the Pattern until they attach to a thread and burst.”
“Light!” It slipped out before Perrin could stop it. Moiraine’s eyes turned to him. “You mean what happened to . . . to Rand is going to start happening to everybody?”
“Not to everyone. Not yet, at least. In the beginning I think there will only be a few bubbles, slipping through cracks the Dark One can reach through. Later, who can say? And just as ta’veren bend the other threads in the Pattern around them, I think perhaps ta’veren will tend to attract these bubbles more powerfully than others do.” Her eyes said she knew Rand was not the only one to have had a waking nightmare. A brief touch of a smile, there and gone almost before he saw it, said he could keep silent if he wished to hold it secret from others. But she knew. “Yet in the months to come-the years, should we be lucky enough to have that long-I fear a good many people will see things to give them white hairs, if they survive.”
The Shadow Rising, Reflection
The effects of the bubble are similar to a trap in Tel'aran'rhiod: each of the men fights what they each hate or fear, yet depend on most.
Rand is afraid of his role as doomed saviour/Dragon and of his destiny to break the world. He is afraid of himself and what he could do to those around him.
Perrin is afraid of his berserker tendencies and lust to kill. The destructive side of his nature is represented by his axe and this is what he eventually ends up casting aside lest it corrupt him. At this stage he barely manages to control it; as we saw in first his mental struggles, and then, as the bubble hit and the axe turned on him, literal struggle.
Mat, whose fears seem almost trivial beside those of Rand and Perrin, is afraid of the One Power (represented by the Amyrlin) and of his luck not being there, and he really dislikes nobility (rulers of the suits).
Incidentally, the omen was wrong: no one died.
By Knife of Dreams, bubbles of evil are almost commonplace.