Silence of the Abyssal Core

The rhythmic thumping that once echoed through the ancient ruin floor dies away as the disembodied heart collapses into a heap of drying muscle and black ichor. Beneath the foul organ, a hidden compartment in the stone dais has been forced open by the demon's necrotic expansion, revealing treasures left by the original temple priests who once attempted to ward off the very evil you have finally vanquished.