I hate to say this, Infernity deck will definitely META at least tier 2 material or maybe even broke to tier 1..sadly the other card in this box are trash.
Sadly they won't, I spent more than 10k in vain. Disastrous match ups against all the meta decks we have and even Aromages and d/d/d keep beating me hard (yes, I have 3 of all the Infernity cards).
Necrovalley can easily be added by Blackwings using the lvl 7 synchro dragon. But yeah, too many disruptions for Infernity to work, and too slow. For all the great effects the deck has when you have no cards, disrupting one crucial play can stop you dead in your tracks.