Garbhodakaśāyī Viṣṇu (stimulation of energy to create diverse forms) and Kṣīrodakaśāyī Vishnu (diffusion of the paramatman or 'supersoul' in the hearts of all living beings) are expansions of MahaVishnu. At the highest level, Vishnu is the formless Parabrahman, and all other deities including Brahma and Shiva are simply expansions of Vishnu.