Amphisbaena

An Amphisbaena is a snake with a head on each end of its body.

The Tower of Nero
An amphisbaena gets on an Amtrak in Washington, D.C. and stares at Apollo and Meg McCaffrey. When it is still on by the time they reach Philadelphia, the mortal god goes it investigate and it snatches his wrist and recites some of the prophecy he heard before leaving Camp Jupiter. It then snaps out of a trance, stating it should haw gotten off in Baltimore before being shot and killed by Luguselwa.

Abilities

 * It can shoot poison from its mouth.