In July 1331/1332, Tzamplakon commanded the Byzantine army's left wing in the defeat at Rhosokastron against the Bulgarians. In November 1332, in his last known act as "megas papias", he co-signed a treaty with Venice. Shortly thereafter, and having already some time before adopted the monastic name Antony, he retired to a monastery where he lived out his days. The date of his death is unknown, but was probably after 1334.