 During the regency of Empress Zoe in 913–919, Leo is recorded as being again Domestic of the Schools and holding the dignity of "magistros".In 917, he was placed in charge of a large-scale expedition against the Bulgarians.The plan involved a two-pronged assault, one from the south by the main Byzantine army under Leo Phokas, and one from the north by the Pechenegs, who were to be ferried across the Danube by the Byzantine navy under Romanos Lekapenos.