In Chapter 18 of Ring Dragonz, Henry, Walsh, Peter, and Sheshen happen upon a long narrow corridor book-ended by two large rusty gates on pulleys.

The boys can only make out some small harmless piles of rocks within (like randomly placed cairns), but are still leery due to their previous unpleasantries down in the Dragon’s Lair.

At Sheshen’s urging, the boys push forward, when all of a sudden …

Dog Rocks.

Like their namesakes, these canines are guard dogs whose bodies are entirely comprised of stones. Rocky Rottweilers. Pebbly Pitbulls. And even Stony Shepherds. These rough puppies usually manage to get the drop on any unsuspecting intruders (just ask poor Henry).