Leviathan and Behemoth in the Bible

Only God (Space Marine) can slay the Leviathan

Behemoth has huge muscles and bones

Possibly like bones of iron (Iron Leaves) (Only God can slay the Behemoth or Leviathan Tyranids)

Scout is Jesus

Space Marine is God

10 horns on a Tyranid Warrior / Termagant

Antichrist allies with the Covenant

Antichrist sets himself in Gods temple

Possibly a temple in Jerusalem / Israel

Horus the Antichrist will set himself up in the Emperors temple (God's temple) whom Sanguinius will overthrow with the breath of his mouth (get in the way of Horus)

Horus will ally with Leviathan, Exodia (Deceiver), Covenant (Dinonids)

Antichrist (Horus) defeats (Sanguinius) and almost Christ (Emperor / God)

Atlantis (Imperium of Man/Homo Sapiens)