Plans to Ambush
An ambush was planned by the Amyrlin Egwene al'Vere as a way to draw the Black Ajah and, more importantly, Mesaana out into a trap. Egwene set up a meeting with several Wise Ones and Windfinders, attended also by Aes Sedai Leane, Seaine and Yukiri; using the meeting about uniting the groups of channelers while Siuan Sanche and other Aes Sedai (among them Brendas, Carlinya, Morvrin, Nynaeve, Saerin, Shevan) "discussed" a plot to bring peace to Arad Doman. The Aes Sedai chosen to participate were those Egwene felt she could trust; they included Egwene's close friends and supporters since she became Amyrlin (Leane, Nynaeve, Siuan);members of the Salidar Six who had sworn fealty to Egwene (Carlinya, Morvrin); her strong supporters among the Sitters (Saerin, Seaine, Yukiri),and other Aes Sedai she trusted (Brendas, Shevan).
Both conversations were fronts to tempt the Darkfriends into eavesdropping but, unfortunately, rather than spying, the Black Ajah outright attacked, beginning a very dangerous confrontation. Two Aes Sedai, Shevan Gadarin and Carlinya Sorevin, were killed immediately.
The plan was for most of the women to leave the battle and wake up, but unforeseen circumstances saw that none of them could leave the city.
In the end, Egwene sent most of the channelers with less experience in Tel'aran'rhiod to an inn to hide. Among those sent out included Brendas, Morvrin, Saerin, Seaine and Yukiri; Brendas was sent out of Tel'aran'rhiod entirely and tasked to wake the others up for safety. Remaining behind to battle were those more experienced: Egwene, Siuan, Leane Sharif, Nynaeve al'Meara, and the Wise Ones Bair, Amys, and Melaine.
Completely by chance, or more likely due to ta'veren bending of the pattern, Perrin Aybara had confronted Slayer in the dream world and stolen a Dreamspike which prevented any instant entrance or exit out of a four-league radius. Perrin took the spike to Tar Valon in the dream to confront Slayer there, creating the barrier around the entire city. Unbeknownst to anyone, this gave the White Tower force a fighting chance against the Black Ajah, as the Black sisters and Mesaana had been planning to lure Egwene and her allies to a preempted location where a trap lay in wait for them. With the dreamspike present, this plan had already been foiled.
Amidst blasts of power and destruction within the dream-White Tower, Egwene finds two Black sisters: Evanellein Lorn and Mestra. Egwene immediately kills Mestra with a ball of fire and then temporarily incapacitates Evanellein by "imagining her to be stupid." However, before Egwene can do any more, Mesaana interrupts, appearing in her cloak of darkness, and tries to force away Egwene's will. Realizing this in time, Egwene then flees to her rooms, meeting Nynaeve.
Nynaeve informs Egwene that the Black Ajah had done something to make many of the halls completely, unnaturally dark. She also tells Egwene that Alviarin Freidhen is present and that another Black sister, Notori, was killed by a blast of fire from Nynaeve. Apparently, the Wise Ones are still fighting in the darkness, seemingly enjoying the battle.
Egwene and Nynaeve then begin to transport themselves to intersections in the dark hallways, back to back in order to spot and attack any enemies. They find Sedore Dajenna right away, who Egwene kills with more fire. Sending themselves to another intersection, they meet Bair, but are interrupted by an explosion of a wall caused by six more members of the Black. It is assumed that Egwene, Nynaeve, and Bair either defeated them or escaped.
Meanwhile, more Black Aes Sedai had been searching the city for the Dreamspike, but to no avail. Mesaana, who is stationed in a room she created beneath the Tower, places her weaves for a cloak of darkness around Katerine Alruddin in order to trick Egwene.
Egwene is still fighting in the halls above when, to her astonishment, Perrin appears. Thinking Perrin to have accidentally stumbled into Tel'aran'rhiod, she attempts to bind him in order to keep him safe from the battle, but Perrin's mastery over the dream undoes this. He then further proves his skills by blocking a stream of balefire with his will, allowing Egwene to kill the Black sister who shot it. Perrin then flees.
Coming to another wall, Egwene can feel two enemies channeling on the other side, and so releases a blast of earth and fire, blowing the wall outward. One of the Black sisters escapes in time while the other, Evanellein, is killed. Mesaana then appears again, prompting Egwene to flee.
To her surprise, Egwene spots the Accepted Nicola Treehill in the fray, likely having stolen one of the sleepweavers in order to come and do battle. Nicola is quickly killed after the ground around her is collapsed. Egwene then spots Alviarin and Ramola a distance away, noticing another wall behind them. Figuring that it is bait for her to attack from behind the wall again, she sends herself there, but facing the room instead. Katerine, disguised as Mesaana, appears, but Egwene wills away the weaves she strikes with. Egwene then throws an Aiel spear at the Darkfriend, willing it to pierce through her shield of air and killing Katerine.
The real Mesaana then appears behind Egwene, snapping an a'dam around her neck and sending the two of them to Mesaana's hidden room below. With Egwene captured, Mesaana orders Alviarin to have the others withdraw. Mesaana tries to interrogate the location of the dreamspike out of Egwene - not knowing that Egwene knows nothing about it - but Egwene resists the pain caused from the a'dam. Then, coming to a realization that the a'dam is simply yet another object in the World of Dreams that is not really there, she wills it to be removed and it falls from her neck. The two then engage in attempting to bend the other's will. Egwene's will proves to be stronger and, almost with ease, breaks Mesaana's mind, dropping the Forsaken to the ground. With Mesaana defeated and the Black sisters already retreated, the battle is won.
Perrin and Slayer
All the while, Perrin is struggling to gain control of the dreamspike from Slayer, with Hopper fighting along his side. After Perrin's encounter with Egwene, Perrin finds Slayer with Hopper in his grasp. He then throws Hopper to the ground and shoots him with an arrow, enraging Perrin and causing him to knock Slayer backward into a nightmare. Here, Perrin has superior control, and so he reclaims the dreamspike from Slayer. After stabbing his enemy in the stomach, Perrin then throws the spike into a rift full of lava, permanently destroying the ter'angreal. Slayer still lives, but with his work done, Perrin wakes up.
Overall, the losses for the White Tower were little, with only three dead on its side. The number of casualties for the Black Ajah, however, is unconfirmed.