Spawning Pool
Zergling is a very strong 1-drop, so being able to generate a couple of them should be a valuable tool in every Zerg deck. When Spawning Pool’s second charge is used, we can also give our summoned Zerg rush, which gives us a way to swing back the board in case we ever fall behind. This is particularly important in Death Knight and Demon Hunter, due to Banelings and Mutalisks.
Score: 3
Zergling
This should instantly become one of the best 1-drops in the format. A Wolpertinger without a beast tag that is available to 4 classes and can be tutored and discounted to 0 mana. Very strong with handbuffs. Mandatory in every Zerg deck going forward but could be powerful enough as a 1-drop in aggressive decks without Zerg synergies at all.
Score: 4
Brood Queen
3 mana 2/5 is slow, though hard to kill on curve. Brood Queen generates larvae that transform into random Zerg minions that can be from any class. This provides some card generation and additional Zerg bodies to activate important synergies, so if there’s a need to maximize Zerg count, Brood Queen should be a good option.
However, the card is admittedly slow and may not be an ideal fit in a deck that wants to snowball the board as quickly as possible. The larvae switch each turn this is in our hand, so we’re not guaranteed to find the best Zerg option for a specific scenario.
If a critical mass of Zerg is needed, it might be the cost Zerg decks will have to pay to maintain enough resources for the later stages of the game.
Score: 2
Nydus Worm
The best draw engine out of the three factions, Nydus Worm adds a discount to the drawn cards, meaning it only costs a net investment of 1 mana. With plenty of Zerg cards being cheap, we might be able to drop what we find immediately to the board, without losing our board initiative. This is particularly powerful with 1 mana cards.
The Zerg are very reliant on staying ahead on the board and leveraging that lead, so having a reload effect that helps us keep up the pressure is very important.
Score: 4
Kerrigan
Kerrigan is another hero card that seems objectively powerful standalone. A 3 damage asymmetrical AOE effect that goes face, on top of summoning two Brood Queens seems like a no brainer investment for 7 mana. If we ever get to turn 7 and have Kerrigan in hand, we will usually play her immediately. It is a very powerful board swing, one that makes Artanis look tame in comparison.
Kerrigan’s hero power is also very powerful, though a healthy number of Zerg is required to fully leverage its damage potential. You can think of it as a permanent Jungle Gym in our hero power that works on Zerg. Could become very important in helping Zerg close out the game, though it might not save our skin if our opponent has managed to take over the board in dominant fashion.
Score: 4