From the introduction:
A long corridor of finely worked stone burrows deep into the earth. Along the walls are beautifully wrought carvings depicting several scenes. In the first scene, a multitude of dragons battle a monstrous creature that emerges from a great rift in the ground. The next scene shows scores of the noble dragons lying dead around the horrid monster.
The third panel shows the living dragons coming together to use two artifacts to cause a massive volcano to erupt from the crevasse and destroy the monster. The artifacts are surprising familiar. In fact, one of them looks exactly like The Heart of Reason. The other looks similar to The Heart of Reason, but seems to have an aura contrary to the one around The Heart of Reason.
The fourth panel tells about how the living dragons gathered in a chamber beneath the newly forged mountain to bury their dead. The scene is one of overwhelming sadness. In addition to the tombs of the dragons, the scene shows a number of dragons sealing the second artifact in a vault covered by a circle of runes. The living dragons seem to be in disagreement over this act and a final dragon is depicted in the background above the volcano flying away with The Heart of Reason.
The fifth and final scene depicts the door that you found leading into this place. It leaves no doubt in your mind that the volcano created by the dragons was Firebelch Mountain and that you are treading upon sacred ground.
That last carving was left in the darkness behind you five minutes ago. The passage before you opens into a chamber illuminated by a shimmering, blue radiance. Dark shadows play across the walls of this place. In the middle of the room, cutting the chamber in two, is a channel from which the radiance glows. Pillars rise out of the channel to reach floor level to form a sort of bridge across the expanse—providing that a would be crosser can jump from the top of one pillar to the next.
User summary:
Into the Dragon's Heart is provided as a 13-page PDF scenario and a 5-page DOC errata; with an additional 2-page DOC handout (print-and-play).