An Abnormality from Project Moon's works (Lobotomy Corporation, Library of Ruina, Limbus Company), appearing in Lobotomy and Library as of 01 Apr 2025.

As the name implies, the Mountain of Smiling Bodies appears as a shambling mound of various humanoid corpses. In Lobotomy it's classified as an ALEPH Abnormality (the highest threat level). If it breaches containment, it will start absorbing the corpses of dead employees into itself, each one giving it a strength and HP buff. In Library it is one of the Abnormalities on the Gebura floor, serving as an allegory for the setting's extreme violence and bloodlust, and is fought both as an individual Abnormality and as part of the floor's Realisation boss fight.