Is this inversion?

Thousands of years ago, we took a wretch from the streets, beaten and discarded. And - blowing upon the embers we found there - we set alight the fires of divinity, at the very heart of the Void. We created the Outsider himself, fellow seekers. A face instead of the endless dark. Black eyes rather than that malevolent emptiness that came before. A voice, speaking to select few, over which otherwise would be the howling of forever. Of nothing without end.
Source: Dishonored: Death of the Outsider, video game

Hi. The “voice” is from a god-like being called “the Outsider” who lives in the Void.

I have previously asked it here.

http://forum.wordreference.com/threads/over-which-otherwise-would-be-the-howling-of-forever.3547607/#post-18035588

But I’d like to know if the underlined clause is a relative clause? Is there any inversion or ellipsis in the clause? Because I would expect, for example, “there would otherwise be the howling of forever over them (overwhelming them)”.

Thank you.