I Don't know why people don't use this deck more often. The surrounding of necrovalley shuts down almost all of the current decks, such as Eldlich, Sky Striker Recursion, Orcust, Borrel, and Salamangreat, while also giving you protection to use handtraps freely. This variant also includes the ability to go super poly into starving and mudragon. This also has an interesting tech against Altergeist, where you can take their monsters for Quintet Magician, then wipe the rest of their board. But basically, the best thing to do search Spiritualist as quickly as possible then go into Supernaturalist with Necrovalley up. Also a good tech is Almarduk to use against Link Spammers.
My favorite thing is to set Spy with backrow floodgates and necrovalley, flip spy to summon recruiter, link into Witch's Apprentice, get the search from recruiter for whatever you need(Spiritualist or other Gravekeeper for fusion) Then go into Supernaturalist. Lowest it can be in this situation is 3700 ATK.