white zombie cards mtg Gluttonous Zombie Token MTG (1/1 White)

It helps that Bloomburrow added many blue and black rats that care about the graveyard and threshold, so you can go that route, too

If youre looking for a budget repeatable option, I like the recent Vat of Bebirth quite a bit if you can enable it

The analyzer counts each from card text and flags exactly where youre short, so you know what to add

At least, as far as we know

It's absolutely great at placing +1/+1 counters on creatures when casting a card from exile

It might not seem like a lot since three mana isnt a huge commitment, but it can mean the difference between playing just one creature face-down and passing, and playing a creature face-down and then being able to flip it back over before your next turn