Zero Hour Hard Achievement

Zero Hour the 3rd level of the campaign is in general a pretty easy mission. You hold up in your base, repair your defenses and finish it off with no problem. At least that is so for the first two achievements on any, and normal difficulties. When it comes to the hard achievement The Best Defense that takes you out of your comfort zone and into the enemy base to destroy their Hatcheries.

It took me a lot of effort to break through the Zerg's tough defenses with a force made of strictly Marines, and Medics. Eventually I gave up on figuring out the assault on my own and resorted to looking up the answer and was quite surprised to find how simple it was.




The video may be a bit hard to understand with his accent but I will highlight the key points to succeeding here.

1. Defense - Make sure your base is always being repaired
2. Supply - Constantly make supply depots, you will want around 125-175 supply
3. Make 2 more Barrack's 3 with reactors, 1 with tech. (I went 2:2 but wasn't as successful)
4. Attack the northern base - The base right above the third group of survivors is the least defended
5. Recuse survivors - They are free units! Rescue the first set, and the third set of survivors. Most likely going after the second set will lose you more units than you will gain.
6. Keep building units! - Even when you are out assaulting the Hatcheries keep making more guys! it is always nice to have a big group waiting when you check back at your base. 

Here is the real trick to beating the achievement and unlocking that final Mar Sara achievement. The northern base though it is the least defended it only has two hatcheries. This is half of what you will need to get your achievement. Simply rush in killing the spine colonies, units, and the two hatcheries. Once you have that done just back off. I chose to sit in the choke point between the east base and where the third group of survivors was found. After a few seconds (I waited 30-45) head back in to find the drones have started rebuilding complete with two easily killed in progress new hatcheries to destroy! That is it! You shoot those two down while they are in progress and you will have your achievement.

A couple notes though. When I did this I went back and only one was being made. Destroyed it, backed off, again came back and the other one was being made. Also I have come up with a much more easily managed way of defending your base. If you are going strictly for the hard achievement this will work best but cause you to lose some buildings and not get the normal achievement.

This defensive setup will make the best use of your bases high-ground, and allow for the least number of SCVs needed to repair the bunkers. When the swarms come they will always be hit by at least 4 of the bunkers and depending on the unit and where they attacks from can sometimes be hit by all 6. This along with a few extra towers for the flying on each side pretty much guarantee a win while only using 4 SCVs to repaid.

Hopefully that will help you grab that last achievement. If you have any other comments or questions feel free to ask.