Ghoulcaller Gisa If you need a lot of bodies on the board fast, and already have a big body willing to sacrifice itself for your noble cause, Ghoulcaller Gisa will spawn the army you need and will snowball if left unchecked
The back face of a meld card still doesn't have any characteristics, however
If you control more than one creature with "This creature can't attack or block alone" they can attack or block together, even if no other creatures attack or block
While were packing a handful of combos centered around Vito and the other Sanguine Bond variants, were perfectly capable of clearing the board (of opponents) with a massive Gray Merchant of Asphodel drain or a freshly deceased Kokusho, the Evening Star
So, if you combine First Day of Class and one of those creatures with a sacrifice outlet, the Persist creature can just be sacrificed as many times in a turn as you want