" Zoe readied her arrows. Grover lifted his pipes. Thalia raised her shield and I noticed a tear running down her cheek. Suddenly it occurred to me: this had happened to her before.She had been cornered on Half-
Blood Hill. She'd willingly given her life for her friends. But
this time she couldn't save us. "

― Rick Riordan , The Titan's Curse (Percy Jackson and the Olympians, #3)