Gregor lay on his back on the cold stone floor, staring at the words carved on the ceiling. This was why they hadn't wanted him to see the prophecy. This was why Luxa had said, "If you want to go home after you read the prophecy, I won't blame you." It was the Prophecy of Time, and as Gregor read it he could hear the ticking of a clock echo softly behind the words. 

"...To the warrior give my blade.

By his hand your fate is made.

While a rat's tongue may be flicking

With its feet it does the tricking

For the paw and not the jaw

Makes the Code of Claw.

Since the princess is the key

To unlock the treachery...

What she saw, it is the flaw

Of the Code of Claw.

When the monster's blood is spilled,

When the warrior has been killed,

You must not ignore the rapping

Of the tapping, tapping, tapping.

If the gnawers find you napping

You will rot while they are mapping

Out the law of those who gnaw

In the Code of Claw."

One phrase echoed in Gregor's brain, over and over "When the warrior is killed....when the warrior is killed....When the warrior is killed...." and Gregor knew he was the warrior. Of course, he could pack up his mother and his little sister and go home to their apartment in New York, far from the Underland, far from the dangers and monsters that surrounded him there. But he would also be far away from friends and fellow warriors, who would be forced to continue the war against the rats.

Gregor knew he had no choice. If he died winning this war, well, so had others. It was not too big a sacrifice to make.