Starcraft II Coop: The game inside the game.

[Winthur]

4-6 worms?? The learning curve here is steep, I'm running 2 and 6 spawning pools.

I'm gonna assume you meant 6 hatcheries (which might be a little bit excessive but I think it mostly comes from Kerrigan having a hard time dumping all of her minerals due to usually being gas-gated, so it's not, like, the worst). 2 worms is fine on smaller / faster maps, 4 worms is easier to manage on maps that take longer, and I usually go 6 worms if the map takes really long, the need for detection is imperative (such as on the current mutation due to We Move Unseen in play) or if I'm playing hero solo.

This is a really neat trick! I was wondering why you would use worms at all with mutalisk/zerglings but tanking with them seems pretty effective.

Even outside of the trick you still want a worm or two with Mutaling because it lets you instantly warp Kerrigan back to your base to play defense, for detection, and for spreading Malignant Creep - for your ally, if no one else (although fully upgraded Raptorlings are theoretically* the best DPS in the game and Malignant Creep only increases that factor). Your ally can also travel with the Omega Worm, though few pubs will be aware of this. Also, worms are nice to have on The Vermillion Problem for popping them next to crystals and shortening Drone travel time. You don't want many of them with an air build, but they're amazing utility anyway.

*They are made of paper, so their primary use is drawing small amounts of fire, chewing on buildings and objectives (Dead of Night in particular), reducing an objective's armor to 0, and, of course, as a mineral dump. They're amazing for cleaning up after an Immobilization Wave (or a Vorazun Time Stop!), but they don't survive much against anything capable of sneezing within distance, unless you're teamed up with Artanis.