- Balon Greyjoy: "I heard you lost your mind during a storm on the Jade Sea. They tied you to the mast to keep you from jumping overboard."
- Euron Greyjoy: "They did."
- Balon Greyjoy: "And when the storm passed, you cut out their tongues!"
- Euron Greyjoy: "I needed silence."
- — Euron Greyjoy matter-of-factly explains how he got silence.[src]
Euron's ship was once caught in a storm on the Jade Sea, far east of Qarth, during which Euron lost his mind: the crew had to tie him to the mast so he wouldn't jump overboard. After the storm had passed and they untied him, he personally ripped out the tongues of his entire crew. When nonchalantly recounting this event years later, he glibly explained "I needed silence" - hence the new name of his ship, for its crew of mutes.
Aboard the Silence, Euron has raided ships from all the Free Cities and across the Summer Sea, including Summer Islander ships and even Ibbenese whaling ships. During this time Euron and the Silence frequently visited the pirate dens of the Basilisk Isles, to sell plunder and take on new provisions.
Euron returns to the Iron Islands, and confronts his older brother Balon Greyjoy on a rope bridge of Pyke castle during a violent storm. Balon recounts the story he heard about Euron losing his mind and cutting out the tongues of his entire crew, which Euron calmly admits to. When Balon realizes that Euron has come to kill him they get into a brief scuffle before Euron throws his brother over the side of the bridge to his death.
- "A bold merchant will risk two years for one voyage to fatten his holds with spices, gems and silks so that he never wants for anything again. To be fair, many never do - because my ship, Silence, finds them on their return."
- ―Euron Greyjoy
In the books
Euron's private dungeon is located below the decks of the Silence. Within it he is fond of cutting pieces off his prisoners and then force-feeding their own body parts back to them. He also has an almost obsessive need to personally cut the tongue out of the mouth of every new crewmember or prisoner he acquires.
For as yet unclear reasons, Euron is also capturing priests from all of the world's religions and holding them prisoner aboard the Silence, torturing them. From a preview chapter from the sixth novel, Euron apparently attempts to use them all as human sacrifices in a mass ritual which will usher him is as a dark messiah of sorts for whatever dark powers he may or may not be in league with. Euron manages to capture his own brother Aeron Greyjoy right after the Kingsmoot and hold him prisoner about the Silence as it advances south to Oldtown, during which time he force-feeds him Shade of the evening, giving Aeron a distorted, psychedelic vision of what Euron intends, part of which involves Euron seated on the Iron Throne, with a shadow in woman’s form, long and tall and terrible, her hands alive with pale white fire at his side, and the gods of every religion impaled on the throne's spikes.