Gameplay in Fatum Betula is an adventure game played in first-person perspective without a user interface, with limited controls used to talk to characters, collect and use items, and open doors.

[2] The player is required to explore to collect liquids to nourish a birch tree that will determine the fate of the world and trigger one of ten unique endings for the game.

[5] Bucher stated that the design of Fatum Betula was strongly influenced by his experiences with the Nintendo 64, stating "the fifth-generation console aesthetic lends itself to environments that are intimate...the aesthetic really lends itself well to creating environments that force the player to engage with them rather than just being set dressing.

Writing for Vice, Patrick Klepek praised the game as "teeming with small details and mysteries" and "design ethos underscored by its PlayStation 1-era aesthetic, full of pixelated textures and blocky character models that aren't as interested in approximating realism as today's games.

"[9] KJ Robertson of Alpha Beta Gamer praised the game as a "fascinating experience", stating the art style conveyed a "real Ghibli-esque sense of mythical wonder to the world.