Anders Behring Breivik on Thursday told a court in chilling detail about how he had planned to kill even more people than the 77 who died in the two attacks he has confessed to having carried out last year.
"The goal was not to kill 69 people. The goal was to kill everyone," he said of the shooting rampage at a youth summer camp held by the ruling Labour Party on an island near Oslo.
In all, 564 people were on the Utoya island when Breivik arrived there on July 22, after he had set off a bomb outside a government building in Oslo that killed eight people.
The prosecution and Breivik's defence lawyer, Geir Lippestad, told reporters that Friday's session would likely be even more painful, since it would focus even more on Utoya island.
"But this is what this criminal case is about, that so many were killed and we have to go through with it," prosecutor Inga Bejer Engh said.
The 33-year-old far-right extremist also testified he had given his murder weapons names from Norse mythology, calling his rifle "Gungnir" after Odin's magical spear and his Glock pistol "Mjoelner" after Thor's hammer.
And he revealed he had once spent a year playing video games, including role-playing online game "World of Warcraft," and a first-person shooting game, to prepare for what he believed would be a suicide mission.
Breivik also practised a form of Japanese meditation daily since 2006 to help block out his emotions during the attacks and said he was still meditating to help him get through the trial.
Earlier Breivik said he had planned for the shooting at Utoya to cause panic, and that he expected people would jump into the icy lake waters and drown.
But when the prosecutor asked why most of his victims where hit by three bullets, Breivik replied: "The aim was to kill, and then you shoot as many times as you need to, until you have achieved that."
He also described plans to capture and "decapitate" former Labour Party premier Gro Harlem Brundtland, who was a guest speaker at the camp that day, and then post footage of the execution on the internet.
Filming killings was "a strategy and tradition among militant Islamists," he said. "It is primarily a psychological weapon that is very effective."
During cross examination, Breivik said that he had also wanted to bomb the royal palace and the headquarters of the ruling Labour Party in Oslo.
"I took many alternatives into consideration but the main plan was to set off three car bombs followed by a shooting attack," he said.
"Making a bomb was much more difficult than I thought," he said.
"It took a lot of time and many problems arose. I lacked materials and had problems with several processes."
The anti-Islamic self-confessed mass murderer said he wanted to attack the palace because the Labour Party used it to host official functions.
Breivik said he considered other locations to carry out the shooting attack, including a journalism conference, as well as the headquarters of Norwegian broadcaster NRK.
"Norwegian media have the greatest responsibility for the situation we have today, even more than the Labour Party," he said.
Prime Minister Jens Stoltenberg - who along with his government was a target of the July 22 bomb that Breivik detonated outside the government offices - tweeted: "Thinking of all of you who are hurting."
Trond Henry Blattmann, who heads a support group for the victims, told broadcaster NRK that listening to Breivik's testimony was "really tough.
"When the details emerge it hits you in the guts. You can't prepare yourself for this."
Blattmann's son died of a gunshot wound to the head at Utoya.
At the start of the trial on Monday, Breivik confessed to the bomb and shooting attacks, but pleaded not guilty.
He told the court on Thursday that he played computer games to "prepare" for the attacks and was also a member of a shooting club.
He also prepared for a possible shootout with police after the bombing attack.
Meanwhile, a German woman expressing support for Breivik was denied entry to his trial and has been deported, police said.
The young woman, whose name was not disclosed, was stopped on the first day of his trial this week at the security controls at Oslo's courthouse, police officer Jan Kvarme told commercial television TV2.
She was held in detention for 24 hours before being taken to the airport on Tuesday and deported to Germany, Kvarme said.
The woman, interviewed by TV2 as she queued up outside the courthouse, said she had promised Breivik she would attend his trial for two
Asked if she and the 33-year-old rightwing extremist had written letters to each other, she replied by nodding her head.