4. L.Fannius and L. lagius served in the army of the legate Flavius Fimbria, in the war against Mithridates, in B. C. 84; but they deserted and went over to Mithridates, whom they persuaded to enter into negotiations with Sertorius in Spain, through whose assistance he might obtain the sovereignty of Asia Minor and the neighbouring countries. Mithridates entered into the scheme, and sent the two deserters, in B. C. 74, to Sertorius to conclude a treaty with him. Sertorius promised Mithridates Bithynia, Paphlagonia, Cappadocia, and Gallograecia, as rewards for assisting him against the Romans. Sertorius at once sent M. Varius to serve Mithridates as general, and L. Fannius and L. Magius accompanied him as his councillors. On their advice Mithridates began his third war against the Romans. In consequence of their desertion and treachery Fannius and Magius were declared public enemies by the senate. We afterwards find Fannius commanding a detachment of the army of Mithridates against Lucullus. (Appian, App. Mith. 68; Plut. Sert. 24; Oros. 6.2, Cic. in Verr. 1.34; Pseudo-Ascon. in Verrin. p. 183, ed. Orelli.)