Svarbhanu, an asura, disguised himself as a deva in order to partake of the amrita. Surya (the sun-god) and Chandra (the moon-god) alerted Vishnu of this deception.
A deceitful asura named Svarbhanu transformed into a divine being to partake in the ambrosia, but his plan was discovered by Surya and Chandra, who alerted Vishnu.