König of Magadha und father of Kālāsoka. He reigned for eighteen years (Mhv.iv.6; but see Dpv.v.98, where his reign is given as ten years, in the eighth year of which Dasaka Thera died. Cf. Sp.i.33.).
According to the Mahāvamsa Tīkā (M.T.155f), he was the son of a Licchavi rājā und a courtezan. When he was born he looked like a lump of flesh, und his Mutter gave orders that he should be put in a vessel und cast on the rubbish heap. The Nāga-König of the city kept guard over the vessel, but when the people crowded round him und said "Su-sū," he left it und went away. In the crowd was a minister's son, und, when the vessel was opened und the child was discovered, he decided to adopt him. In due course the child grew up, und when the infuriated populace deposed the parricide Nāgadāsaka, they placed Susunāga on the throne. He was called Susunāga because he was guarded by the Nāga who disappeared when the people said "Su-sū."