Ok I'm doing a rotation proof/budget Zombies-I understand Cryptbreaker and co would be good, but I won't be going there. This is NOT for tournament play.
Sacred Cat and Sunscourge Champion might be maindeck or sideboard considerations as their resurrection ability adds the zombie type. They also happen to be resilient and gain life against the aggressive red decks coming out.
Time to Reflect could be an ideal, cheap removal spell with your deck focused around zombies. Not many people will think about it and it will always be on their mind afterwards.
Shefet Dunes / Ifnir Deadlands by themselves or combined with Dunes of the Dead are other substitutions. Dunes of the dead would need testing to see if your deck could handle an early colorless mana. The other two, however, give your deck an additional push when you run out of cheap creatures.
Edit: Also, be careful with Supernatural Stamina if Magma Spray is prevalent. Your 2 toughness creatures will be exiled (rather than die) so the saving effect won't trigger.
4 Dread Wanderer
4 Wayward Servant
4 Binding Mummy
4 Mummy Paramount
4 Lord of the Accursed
2 Plague Belcher
2 Metallic Mummy
2 Supernatural Stamina
2 Never/Return
3 Liliana's Mastery
1 Throne of the God-Pharaoh
10 Plains
Any other cards Kaladesh onwards that would fit?
Time to Reflect could be an ideal, cheap removal spell with your deck focused around zombies. Not many people will think about it and it will always be on their mind afterwards.
Shefet Dunes / Ifnir Deadlands by themselves or combined with Dunes of the Dead are other substitutions. Dunes of the dead would need testing to see if your deck could handle an early colorless mana. The other two, however, give your deck an additional push when you run out of cheap creatures.
Edit: Also, be careful with Supernatural Stamina if Magma Spray is prevalent. Your 2 toughness creatures will be exiled (rather than die) so the saving effect won't trigger.