Fall of Reach - Armor Piercing Rounds

They entered the room. The large window was a half-meter thick. It overlooked a large chamber that descended three decks. A cylinder ran the length of the chamber and red light pulsed along its length, like a liquid sloshing back and forth.…

… “I’ve got an idea.” Sam limped forward. “Hand me those warheads.” John did as he asked, so did Kelly.

“We shoot out that window, set the timers on the warheads, and toss them down there. That should start the party.”

“Let’s do it before they call in reinforcements,” John said. They turned and fired at the crystal. It crackled, splintered, then shattered.

- Halo: The Fall of Reach, Chapter 14