Emusha form of Vishnu is the celestial boar. In this divine incarnation, Vishnu ploughed up the earth, which was lying under the cosmic waters. Emusha is also another name of Varaha.
As per some accounts, Emusha ploughed up Mount Meru with his might tusks and brought it to the surface. This was later used by Asuras and Devas for the cosmic churn.
Emusha is a name also found in the Rig Veda, Satapatha Brahmana, Atharva Veda and Taittirya Samhita and Kathaka Samhita. Here too a big bar whose flanks stretched across raised earth up.