“Close!” he moaned. “So close, but gone!”
It broke Percy’s heart to hear the pain and worry in the big guy’s voice, but he knew they only had a few seconds to talk. The edges of the vision were already dissolving. If Alaska was the land beyond the gods, Percy figured the farther north he went, the harder it would be to communicate with his friends, even in his dreams.
“Tyson!” he called.
The Cyclops looked around frantically. “Percy? Brother?”
“Tyson, I’m okay. I’m here—well, not really.”
Tyson grabbed the air like he was trying to catch butterflies. “Can’t see you! Where is my brother?”

The Son of Neptune, Chapter XXXVII