ZERUS MISSION 1: WAKING THE ANCIENT
Main Objective: Feed the Ancient One [0/7], Brakk Can't Destroy 7 Quillgor Biomass [0/7], Kill Brakk
Bonus Objective: Absorb Primal Essence [0/3]
Waking the Ancient: Complete the "Waking the Ancient" mission in the Heart of the Swarm campaign.
A Game of Drones: Don't lose more than 3 Drones in the "Waking the Ancient" mission.
Rude Awakening: Kill 4 Primal Hives in the "Waking the Ancient" mission on Normal difficulty.
The first biomass will be directly to the right of your base. It is easily taken with the small group of units that you start with. Be sure to start spreading creep now, as there is not much else to do, and it will help alert you of incoming attacks on the minimap later on.
The second biomass will be to the southwest of your base. There still isn't a huge need just yet to start massing units, so making a macro hatchery with extra minerals will help with saturation and unit production later on. Clear it as fast as you can so you can start on your expansion.
Building Mutalisks vastly improves the mobility of your army. There will be small groups of primal zerg that will attack your base from the northeast and the southwest. Having a highly mobile army early on will help you defend your base if you're ever caught by surprise while venturing far away.
The first Primal Essence is located southeast from the Ancient One. If you haven't already, start researching upgrades for your air and ground units. Brakk is extremely strong and makes short work of your units.
The second Primal Essence is located in the southwestern most corner of the map. At this point, I would start adding roaches into your army composition while still increasing your mutalisk count.
The third and final Primal Essence is located in the northeastern most corner of the map. Adding Abberations to your composition is suggested in order to clear out the Primal Hives for the Rude Awakening achievement.
As it can be seen on the minimap, there is a primal hive southeast of the ancient one. Your army, which should be close to maxed, should be strong enough at this point to clear out the remaining primal hives without any problems. Do this before you finish collecting the biomass, as that signals Brakk to start his attack.
The second primal hive is south west of the one that was just destroyed.
The final two primal hives are right next to each other at the southeastern most corner of the map.
After delivering the final biomass, a cutscene will start and signals Brakk's final attack. He starts from the southeastern most corner of the map and makes his way directly towards your base. Gather the rest of your forces and simply wait at your base for him to arrive. With a maxed out army he should be easily dealt with.