Moss was Polyarc's debut game, developed by a 14-person team assembled from veterans of Destiny, Dragon Age, Guild Wars, and other major franchises. It was released for PlayStation VR in February 2018, for Oculus Quest in 2019, and for SteamVR in 2020. In the years since, it has accumulated 94% positive reviews on Steam from 1,783 users, a Metacritic score of 81, and nominations across every major gaming award: three BAFTA nominations (Game Innovation, Best Original Property, Best Debut Game), nominations at The Game Awards, Golden Joystick Awards, Annie Awards, IGF, and GDC. It is one of the most decorated debut games in VR history.

The premise begins with you literally opening a book. Sitting in a great hall before an enormous ancient tome, you turn the pages to discover the legend of Quill, a young mouse living in a world called Moss. When Quill's uncle is taken by a demon serpent called Sarffog, her discovery of the Relic — a mysterious artefact — summons you: the Reader, a glowing orb who exists in Quill's world as a disembodied spirit. You become her companion, guide, and protector. The storybook framing never drops: the game constantly returns to the book, and the narration is delivered as if being read aloud by an unseen voice.

Quill's ASL-inspired gesture vocabulary is also worth noting: she uses a form of American Sign Language to communicate with the Reader throughout. This was developed with input from the Deaf community and allows Quill to express herself, give hints, celebrate, and acknowledge the player's presence without any dialogue. It adds to the extraordinary sense that she is a real, present individual rather than a game character.