A Terracotta Automaton is a magical or mechanical construct believed to have once been used as infantry in the armies of Grand Cathay. Their humanoid bodies are made primarily out of clay.[1b]
In 1310 IC, a Cathayan army comprised of massive numbers of Terracotta Automatons were used to hold back hordes of Chaos Warriors trying to break through the Great Bastion of Cathay.[1b]
The Terracotta Sentinel presently used within the Grand Imperial Army of Cathay is presumably a larger version of those ancient Terracotta Automatons.