It’s the final mission of the game! This mission is unique because every single unit that Mengsk creates are specialized named groups of mercenaries.
Among the worst to deal with are the medivac/reapers who can take out an entire army by themselves if Kerrigan is around to carry weight.
Luckily for this mission you have Kerrigan and she kills everything very easily, even these hero units.
This mission is more about numbers and less about composition. You will need to have something to soak tank blasts (zerglings, ultralisks, abberations, or roaches) and you will need to diversify between range and melee range units. Flying units have largely been useless in this mission, despite there being two giant hero waves of air units.
In this map there are three Zerg entry points you can unlock. They are unlocked by destroying the bunkers in front of them. Two of them have planetary fortresses guarding them. A great and easy solution to this is to roll banelings into them. Combined with the splitter upgrade these banelings will get rid of all these static defenses cost effectively.
The mission has two achievements.
Achievement: Swarm Guardian
This achievement merely asks that Raynor’s Hyperion does not take any damage. This is a relatively easy thing to accomplish and on Brutal it is very important to protect Jim anyway.
Unlike in other difficulties, on Brutal none of your allies really carry their weight. After releasing any of the three Zerg leaders they wil launch a massive force that will all die to one round of tank fire. James Raynor is equally useless as each of his attacks is immediately quashed.
The attacks by the enemy have a timing. After James Raynor sends his forces forward and loses all of his forces he will immediately get counter attacked by Mengsk. The first wave is a group of banshees and vikings, the second wave is battlecruisers and siege tanks, the third wave is an Odin with Goliaths.
To deal with the first wave your unit of choice will be the LURKER! Yes it’s finally useful. Create 4-5 lurkers and place them at the entrance of Raynor’s base. Once Mengsk sends his first group to kill the Hyperion, slightly move them a little north of the bunker. All of the vikings will land here and immediately die to lurker damage. Raynor’s thors can deal with the banshees very effectively, as can marines.
The second wave you will need to either bring Kerrigan or hydralisks. It is also possible to intercept this if you have made enough progress with destroying Mengsk’s base. The frenzy ability is particularly useful in adding extra damage.
The third wave is the Odin. This waves is the easiest and can be destroyed simply by dropping a spawn baneling on top of Odin which will kill all of the goliaths. After that you merely attack him head on with your army and he dies very easily.
If you defeat these three waves Mengsk will not do anymore attacks that can destroy the Hyperion.
Achievement: Speed Bump
Speed Bump is not accomplishable with Swarm Guardian. Unfortunately the timings work out so that if you are attacking aggressively into the enemy, you can’t save Jim.
Speed Bump benefits very heavily from a fast max tactic. Fast maxing generally involves high amounts of roaches mixed in with some zerglings. As you push forward you can start mixing in hydralisks as more of your army dies out.
You should have Spawn Banelings for the fast burst damage (with splitting banelings), the single target nuke ability, having the ability to Crushing Grip will be great or area of effect single target is amazing as well. The Pod ability is useful but the area of effect damage spell can also be useful.
You should make sure to have your abilities on CD almost at all times. You can use Kerrigan to do some damage by herself a lot of the times without risking too much of your army.
Head northeast with your army, this is the path of least resistance.
Upon getting this achievement you will also get the Mastery which involves killing Odin before he gets to Raynor.