Heart of the Swarm Campaign- Kaldir: Harvest of Screams (Part 3)

The second close spire is to the West, but it is protected by the main Protoss base nearby- be very careful when attacking it and take full advantage of the flash freezes to take out pylons first, disabling the enemy detectors.  If you’re fast you can also take out the enemy nexus and probes, putting a huge dent in the number of Protoss attackers you have to stop from ruining your base.  Fighting during flash freezes only, expect this base to take two to three freezes to destroy- the buildings are numerous and well-protected by both units and cannons.  You would be well served here to simply rush in and obliterate pylons rather than destroy the whole thing, unless you’re in dire need of the mineral patches behind the enemy nexus (which you should always destroy even if you’re not interested in blowing up the whole base- resource denial is always important).

The final Protoss spire waits in the Southwest, behind the secondary Protoss base.  This is the harder of the two assaults, not because of the number of enemy troops but because of the cluttered space the outpost is built in.  Your units are likely to get in one another's way here, which makes it a good idea to mix unit types between melee and ranged so that nobody is blocking anyone else out.  To make things worse, the spire itself is up a ramp on a raised area, and there’s an enemy colossus waiting there, set to destroy waves of your attacking units with its area lasers the moment they mount the ramp.  Unless you have Kerrigan in the lead to hit it with a Kinetic Blast immediately, you’re best served by waiting for a flash freeze- it’ll guarantee you have enough surviving units to actually take out the spire in a timely manner.  Of course, this is probably the last target you have, so you may not care that the colossus will rip holes in your front line.  If this is the case feel free to go ahead anyways- just be aware that it's not the cleanest, fastest, or most efficient way to handle things here.

The end of the mission is a touch anticlimactic- basically just consisting of Sarah confirming that she's won.