Whether the nebulous archer possessed a soul core or not, they were still a shadow. That was how they had been able to survive in the Shadow Realm, and why they were hunting the shadows of living beings for sustenance.
That was also the reason why this cold and ruthless slayer could influence the wild shadows populating the desolate land, so much so that they were even scared to answer Sunny's call.
However…
Since the archer could interfere with Sunny in that way, didn't that mean that Sunny could do the same?
After all, the archer was a shadow.
And Sunny was the Lord of Shadows.
He held dominion over everything that was a shadow, whether they liked it or not. If Sunny so wished, he could control and manipulate shadows, manifest them into tangible forms, or even send them into the Shadow Realm and back.