Hi Patty,
If the seed of Satan was to be in the flesh, there is the possibility that Satan could father the child himself that would be the Antichrist, and it would have a human mother. A second possibility would be a clone of Satan (DNA of Satan inserted into a human female's egg) which would produce the Antichrist. The third possibility is the theory that Doug Hamp came up with. He is the author of the book called Corrupting The Image. He thinks that Satan will insert his own DNA into the person who is to be the Antichrist, and the Antichrist's own DNA would be changed.
As for Pastor Riley, he thinks that Lucifer in Isaiah 14:12 is the Antichrist because Satan can't be killed and the person in Isaiah 14:19 is cast out of his grave, and thrust through with a sword. However, both the beast and the false prophet are cast alive into the lake of fire according to Rev. 19:17 so it doesn't sound like the Lucifer mentioned in Isaiah 14 is the Antichrist unless Isaiah 14:19 is referring to the beast (Antichrist) in Rev. 13:12 whose deadly wound is healed and the same beast in Rev. 13:14 which had the wound by the sword and did live.  So I don't know if Pastor Riley's theory is correct or not.