Caturvyūha
Caturvyūha or Chatur-vyūha (Sanskrit: चतुर्व्यूह, romanized: Caturvyūha, lit. 'four emanations'), is an ancient Indian religious concept initially focusing on the four earthly emanations (Vyūhas) of the Supreme deity Nārāyaṇa, and later Viṣṇu. The first of these emanations is the hero-god Vāsudeva, with the other emanations being his kinsmen presented as extensions of Vāsudeva himself. From around the 1st century CE, this "Vyuha doctrine" (Vyūhavāda) developed out of the earlier Vīravāda cult of the Vrishni heroes, in which the five heroes Saṃkarṣaṇa, Vāsudeva, Pradyumna, Samba and Aniruddha had remained mostly human in character. Still later, around the 4th century CE, it evolved into the Avatāravāda system of incarnations of Vishnu, in which Vishnu was the primordial being and the Vrishni heroes had become his avatars.
The "Four emanations"
Front: Vāsudeva (center) and his kinsmen emanating from him. Vāsudeva is four-armed, and is fittingly in the center with his decorated heavy mace on the side and holding a conch, his elder brother Balarama to his right under a serpent hood, his son Pradyumna to his left (lost), and his grandson Aniruddha on top.