Nat select, plasma, rippers, aggro with lots of removal or displacement like cass as this will struggle trying to cram more healing in as it’s very awkward for its gameplan, any deck with decent AOE shuts down progenitor hard, decks with answer or die threats as this almost completely lacks answers and if you try to cram answers in the decks already awkward to pull off plan gets much harder.
It’s doing well right now because no one wants to play Vaath because of kha, no one wants to play answer or die because of Sand/BOA, there is very little swarm so AOE is kind of light, and Aggro is being teched agasnt a lot right now so it’s sort of on the back foot other then tempo Ziran which is bad versus this.
And even now Ragnaora in general can tear it up pretty bad just thanks to rippers. It’s a pretty dang good choice for this miserable meta that we have, but it has so many down sides the fact that it’s a decent anti meta deck is not worth an investment. If you just have the stuff and want to play the meta game even though there are things that make you fold hard then that’s fine, I hate getting countered that hard, and if the meta shifts at all the deck could very quickly go back to being pretty bad rather then being the niche counter propped up by rag that it currently is.