Pauper Zombies. It's a race to the end with these bad boys, but don't fear the reaper here, the clock is on your side as you can gain your life back with the Gray Merchant. Let's start with the one drops and work our way up from there:

Shambling Goblin and Festering Goblin both play nice as one drops that trade for value and act as removal.

Carrion Feeder grows nicely when you sacrifice your beaters, it also plays nicely with your gobbo zermbies to help clear they way for attacks.

Carnophage is pure aggression, but don't worry about his downside, you are racing the clock to kill your enemy and can sacrifice some life to get there.

Sangrophage is great devotion points for Gray Merchant of Asphodel, but even better is an aggressive body that puts the pressure on. 2 life a turn, pfffft.... Who needs it?!? Not you when you run this in your deck.

Shepherd of Rot is a good closer if you are ahead on life, just be wary as he bites you as hard as he does your foe.

Ghoulraiser is awesome card advantage as well as devotion needed to gain you life later with Gray Merchant of Asphodel. All upside here, just a good solid cornerstone to the decks longevity.

Embalmed Brawler can help bring the pain if you have made it grow, it's high costed but worth the play since we have so many zombies in the deck to reveal.

Gray Merchant of Asphodel brings Theros devotion and lifegain to the deck. He makes all our downside cards worth playing as the life swing he gives often just finished the game, but also counters all the self mutilation we have been doing.

Gempalm Polluter is a burn spell, not a creature, you won't hard cast this zombie if you can avoid it. It provides burn and card advantage.

Gurmag Angler is a nice closer, all your expendable zombie horde can fuel the Angry Angler to delve out a 5/5 zombie fish. I tend to side this out in control matches as you don't want to exile your graveyard in those matches.

Sideboard

Grasp of Darkness and Victim of Night are powerful removal for games that you aren't trading well in. Grasp is good for most things as it can reduce them enough for a combat trade or post combat, but victim of night is better against things like Atog in Affinity that get out of control big.

Tendrils of Corruption for life gain and stompy creatures like angry anglers that your other removable misses.

Ghoulcaller's Chant for more control matches instead of your zombie gobbos. Every card is a zombie, so bringing two back (especially ones like Ghoulraiser) brings back breaking value against edict and removal heavy decks.

Sylvok Lifestaff provides a cheap buff that makes trading much more comfortable with some life gain. Also this is a great way to keep up with grindy control decks as its cheap, so are your zombies, so every removal and edict gives you the health you need to keep up your pain zombies.

Oubliette is hard to remove and adds that sweet devotion while neutralizing nightmare creatures like Atog, Gurmag Angler, etc.

Pestilence is here because we don't care about our creatures or life total, but we sure as hell don't want to be in a race with go wide strategies either. More often than not some of our stuff will survive as the 1/1s and 2/2s fall off to the wayside. This card is a beast and bumps up our devotion when we keep it on board.