In the fall of man, the key conflicts of our age
have been set off.

The serpent of the old has successfully drawn mankind into conflict with the Lord our God. Now on one hand, Satan is described as the the god of this age.

“among whom the god of this age has blinded the minds of those who do not believe so they would not see the light of the glorious gospel of Christ, who is the image of God.”
2Cor 4:4 New English Translation,

Here the New English Translation copyright 1995-2005 is more accurate in translating this as “age” (ai?n), but it is sometimes translated as “world.”

“Now is the judgment of this world. Now the prince of this world will be cast out.”
Jn 12:31 WEB

Here the regular word for world is used, kosmos. And Satan has enough power to deceive the whole world.

“The great dragon was thrown down, the old serpent, he who is called the devil and Satan, the deceiver of the whole world. He was thrown down to the earth, and his angels were thrown down with him. ”
Rev 12:9 WEB

“We know that we are of God, and the whole world lies in the power of the evil one. ”
1Jn 5:19 WEB

So God ordained that there be opposition, hostility,
between the woman, and Satan.

““I will put enmity between you and the woman, and between your offspring and her offspring. He will bruise your head, and you will bruise his heel.””
Gen 3:15 WEB

Now it speaks of warfare between the seed/ offspring/
descendant, of Satan,

and the offspring of the woman. But the Hebrew word (zera) is here singular in both cases. The hostility is between the singular descendant/seed of woman, and the singular descendant/seed of the serpent.

As the fall came through the woman,

so also came the deliverer (Jesus the Christ, the singular seed of woman) through the woman (not through the man).

“4 But when the fullness of the time came, God sent out his Son, born to a woman, born under the law, 5 that he might redeem those who were under the law, that we might receive the adoption of children.”
Gal 4:4-5 WEB

The word that is translated as “bruise” in the WEB and KJV in Gen 3:15 can also be translated as to snatch or grab or seize or a blow per the Hebrew Aramaic Lexicon of the Old Testament, Koehler and Bumgartner, 1994,2000. Surely the Bible in Basic English 1965, gives the sense of that last phrase in Gen 3:15 as well as any:

“by him will your head be crushed and by you his foot will be wounded.”

And the “seed”/offspring of Satan?

He still remains to be revealed in our own day, as it was with the Thessalonians (2Thes 2:6). He is what 2Thes 2:3 calls the “man of lawlessness,” and what Revelation calls “the beast.”

So Gen 3:15 is still in the process of being fulfilled.

KJV is the King James Version, 1611.

WEB is the World English Bible, a copyright free revision
of the original ASV American Standard Version 1901