Last weekend, I played a small trial, which consisted of four rounds, well, the first time I played something competitive after I moved the deck again. And I subsided with the result, which was 3 victories and a defeat, almost made top 4, but lost in the tiebreaker. I am going to play next to Eternal here in my region, where they play at least 40 players, and I have good expectations for the deck.
+1 Unholy Grotto: The reason to opt for one more of this card, was by the strong combination with Nameless Inversion and Gempalm Polluter. why so, it helps me to control more the creatures that come into play, and cause more damage to the opponent. I think it's a strong move.
Nameless Inversion: This card has a power less than Fatal Push, but for this tribe it is likely to be the most useful removal. because it is profitable by Unholy Grotto, and counts in the graveyard with Diregraf Colossus, and with this creature in play, still places a Zombie token. And off it's great against almost all other tribes, elves, goblins, merfolks. But it is very weak against Eldrazi.
Diregraf Colossus: Since the deck does not have so many creatures, then using a lord becomes a bit unfeasible, but this creature fits very well, and that's a good card against Chalice of the Void, the magic is interrupted, and with Gempalm Polluter, it causes a lot of damage, ending the game faster.
Gempalm Polluter: This Zombie I quite like. has a very strong ability. purchase letter and cause damage. And even if it does not cause much damage, still graveyard for Diregraf Colossus, it can be used back with Liliana, the Last Hope.
In my opinion, the deck loses efficiency with a lack of more discads, but I've moved cards that have this effect to the SideBoard. But the Zombies became more synergistic, with more interactions, and ended up getting stronger in the case of creatures, but if I really did, I would use Inquisition of Kozilek, but I chose to leave the deck with more speed, using Dark Ritual. The deck was more fun, but I hope you get more results too.