Having headed back to ground while the Raiders and Valerian left under heavy fire, Kerrigan is forced to deal with Dominion forces as she searches for Jim. The massive cannon that she has found is a major threat- it will shoot down any incoming ships, including Raynor's, so you're going to have to work with the leftover bits of a Zerg brood to overcome the Dominion forces here.
You have fifteen minutes to go before reinforcements arrive, and you're located in the Southwest corner of the map. You have only a hatchery, an evolution chamber, and a few defensive structures. Sarah will guide you at first, pointing out that you need a spawning pool to create zerglings. While the game does tell you where to build it, you don't actually need to listen, so don't worry about that.
More interestingly, the brood mother that controls the brood Sarah has found will point out three caves nearby, which contain one or two queens and a small cluster of zerglings each. These caves are being bottled in by Terran forces, which you can kill to gain access to the zerg contained within. While the caves to the North and East are relatively simple, each protected by a bunker and perhaps a few mechanical units, the one to the Northeast is actually 'behind' an entire Terran base, which you will have to smash through in order to reach it. Because of this, you should probably save that cave for last. Keep on your toes, as every so often a force of ground units or two-three wraiths will assault your base. If it's not adequately defended, you can lose a lot of buildings and units to this, despite your creeper colonies.
If you like, you can go to the trouble of protecting the infested buildings near the edges of the Zerg colony, but they actually help you more when you let attacking Terrans destroy them- each building will release four to eight broodlings when destroyed, which will attack any enemies nearby and then charge blindly for the Terran base in attack mode. Moving up your own units behind them to use them as shock troops can give you the necessary advantage to keep more of your zerglings intact and deal damage more quickly to enemy emplacements.
These offensive forces are coming from the Dominion outpost that guards the central cave, so if you find the attacks to be too much of an issue, you can head directly there to destroy it. It will be a bit of a trial though- the Dominion has access to not only firebats, but also hellbats- and between those and the wraiths, your zerglings are going to be in a lot of trouble. Queens will go some way to alleviating this but their healing power, Transfusion, is mostly wasted on zerglings- it heals more health than they have total, and consumes rather a lot of energy. Further, zerglings tend to die faster than the queens can use the healing ability, so if you’re going to lean on queens, it’s better to do so heavily and use them as ranged assault troops as well as healers. Kerrigan will be your main source of damage, really, with Kinetic Blast dishing out more hurt than anything but a structure can take. She’s also your key for bringing down wraiths, as queens’ damage is subpar, though they make an excellent wall between their fairly high health and Transfusion.
