“Percy!” Annabeth said. “Can you talk to that thing? Do you know what it is?”
The son of the sea god shook his head, clearly mystified. “Maybe it’s just curious about the ship. Maybe—”
The monster’s tendrils lashed across the deck so fast, Leo didn’t even have time to yell, Look out!
One slammed Percy in the chest and sent him crashing down the steps. Another wrapped around Piper’s legs and dragged her, screaming, toward the rail. Dozens more tendrils curled around the masts, encircling the crossbows and ripping down the rigging.

The Mark of Athena, Chapter XXIII