Immediately after the Fall of mankind and all creation into sin, God promises a deliverer who will defeat the greatest enemy once and for all.
Genesis 3:15
15 And I will put enmity
Between you and the woman,
And between your seed and her seed;
He shall bruise you on the head,
And you shall bruise him on the heel.”
New American Standard Bible: 1995 Update (La Habra, CA: The Lockman Foundation, 1995), Ge 3:15.