YOU are an incarnation, if you want to say like this. In reality there is no separation at all between you and God, but because it seems so this word is used.
Nephilim refers to the animal nature in man, it refers to the common state of human beings trapped in samsara - the wheel of life. This is why I say humans are the lower self or fallen angels, or in other words the Lower Self is meant.
Angel, incarnation, Buddha, avatar, all these things mean one who has freed himself from samsara, who has become a celestial or enlightened being. Now, they reside in heaven, they have gone into nirvana, or experience moksha - all these simply mean to realize the Higher Self.
To say directly: man has died that god can be, or fallacy has been dropped and truth realized. The goal of all religions has been realized.