Inspired by natural processes, Protomycokion is a sustainable building component created from renewable biomass. Waste fibres are transformed by fungal mycelium: the living material is 3d printed as an algorithmically designed column. This results in a resilient construction material that is structural, waterproof, sound absorbing and highly haptic. Employing 3d printing and computational design, Protomycokion brings closer the era of mass-customization where homes can be as expressive as the people that inhabit them, responsive to diverse contexts, changes of use, and cultural preferences.