Supposedly, someone discovered a ritual that will link all wearers of masks from a ritually prepared pack, enabling them to share each other thoughts.
Some tellings of the tale have it so, that this is not mere surface level telepathy, but dives deep into beliefs and values which are being shared across the community of mask weares.
Yet others insist, that, while the mask ritual does exist, it has nothing to do with thoughts or beliefs, but with health that is being shared.
Some get more concrete than that, explaining that health is to be understood as breath. That as long as one wearer takes a deep breath, all others will partake in a share of it.