Board Thread:General Discussion/@comment-30406012-20180830141225/@comment-28362353-20180830143933

Jiren is most definitely capable of erasing a universe. Beerus vs BoG SSG Goku almost annihilated the entire universe just from their fists colliding. Jiren is way stronger than BoG Goku, and he's also stronger than Beerus. So there's no reason to assume Jiren couldn't destroy the universe if Zamasu fused with it.

Also, as we saw in the Manga, a Hakai from Goku (which would be way weaker than a Hakai from Beerus) almost erased Zamasu, so Zamasu can be erased by Black Saga Goku, and Jiren is WAY stronger than Black Saga Goku, so its clear Jiren is very capable of erasing Zamasu from existence.