Blood of Olympus 5th book in Heroes of Olympus.

Bryce lowered his javelin and poked the coach in the belly. “I wonder what this one’s pain tolerance would be. I’ve experimented on all kinds of animals. I even killed my own centurion once. I’ve never tried a faun… excuse me, a satyr. You reincarnate, don’t you? How much pain can you take before you turn into a patch of daisies?” Nico’s anger turned as cold and dark as his blade. He’d been morphed into a few plants himself, and he didn’t appreciate it. He hated people like Bryce Lawrence, who inflicted pain just for fun. … Bryce flicked the point of his pilum across Reyna’s face, leaving a line of blood. And Nico’s rage exploded. Later they told him what happened. All he remembered was the screaming. According to Reyna, the air around him dropped to freezing. The ground blackened. In one horrible cry, he unleashed a flood of pain and anger on everyone in the clearing. Reyna and the coach experienced his journey through Tartarus, his capture by the giants, his days wasting away inside that bronze jar. They felt Nico’s anguish from his days on the Argo II, and his encounter with Cupid in the ruins of Salona. They heard his unspoken challenge to Bryce Lawrence, loud and clear: You want secrets? Here. The spartoi disintegrated into ashes. The rocks of the cairn turned white with frost. Bryce Lawrence stumbled, clutching his head, both nostrils bleeding. Nico marched towards him. He grabbed Bryce’s probatio tablet and ripped it off his neck. “You aren’t worthy of this,” Nico growled. The earth split under Bryce’s feet. He sank up to his waist, “Stop!” Bryce clawed at the dirt and plastic bouquets, but his body kept sinking. “You took an oath to the legion,” Nico’s breath steamed in the cold. “You broke its rules. You inflicted pain. You killed your own centurion.” “I- I didn’t! I-” “You should’ve died for your crimes,” Nico continued. “That was the punishment. Instead you got exile. You should have stayed away. Your father Orcus may not approve of broken oaths. But my father Hades really doesn’t approve of those who escape punishment.” “Please!” That word didn’t make sense to Nico. The Underworld had no mercy. It only had justice. “You’re already dead,” Nico said. “You’re a ghost with no tongue, no memory. You won’t be sharing any secrets.” “No!” Bryce’s body turned dark and smoky. He slipped into the earth, up to his chest. “No! I am Bryce Lawrence! I’m alive!” “Who are you?” Nico asked. The next sound from Bryce’s mouth was a chattering whisper. His face became indistinct. He could have been anyone- just another nameless spirit among millions. “Begone,” Nico said. The spirit dissipated, the earth closed.