Dev builds fully code-animated robotic biped in Unreal 5.8 with Fable 5.2 in 2 days

iamrobotbear · x · 2026-11-13

Developer @pingouh used Fable 5.2 to tackle a coding task he considered impossible alone: complex behaviors for a creature.

Started as a Three.js prototype of a little robotic biped living its own life, animated entirely by code — extensive movement research to get it walking, running, and galloping without falling, feet that plant on the ground, and a head/neck that actively looks around; hundreds of simulated runs were used to find and fix trip points.
He then ported it to Unreal 5.8 and made it controllable with a PS5 controller. No pre-recorded animation — everything is computed at runtime.
The whole thing took 2 days (sound design admittedly rough).

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