Powered up Termagant's

You want Clogged with Corpses, another Spore Sac and Termagant Sentry. These are easily some of the best cards available to Swarmlord. No Mercy is pretty good too.

 

I think you'll have trouble making the Harpies work. Same with Digestion Pool and Sacaellum Infestors. You can probably cut at least one Spiker and a Strangler Brood as well, but you really want to include three more 3-drops with hammers.

Mostly agree with syntax, especially re: cards to try and squeeze in, I think harpies are okay with 9 sources of infest (assuming you add another spore sacs), but digestion pool and infestors become pretty unreliable - even if you manage to infest a planet for pool you might not want to have to deploy a unit there every turn just to get the discount and it's inefficient if not being used constantly. Similarly it's unlikely you'll get investors to click every turn and given how quickly games can end, you don't want turns when it's not firing, as it's a momentum and R/C hit to play in the first place.

Thank you for your suggestions.

I've made the following changes based on your feedback.

Harpies are a lot worse without Venomthrope Polluter and Dark Cunning. Especially when you want to also generate value with Swarmlord's reaction. Also, you really want to aim for 51 cards. It's hard to make the cuts, but it's always better.