Sorry, Ixalan, Ikoria has you beat
Pestilent Souleater Pestilent Souleater is on the bottom of the list because you have to pay phyrexian mana (2 life or ) every time you want to give it the infect ability
Combined with Super Shredder's menace, this rapid growth translates into an extremely fast and difficult-to-block clock, making Super Shredder a quietly potent addition to the Dimir Shadow archetype
Yet, Tombstone Stairwell has spiked from $14 to $82
Scute Swarm, Hornet Nest, Hornet Queen, Giant Adephage, and Moldgraf Millipede are all great choices
For those of you who are interested, here are some of the Scryfall searches I used to write this article: Cooper Gottfried Cooper is an ecological researcher, currently studying animal migration