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Starcraft 2: Wings of Liberty Walkthrough Mission 7: The Great Train Robbery
Starcraft 2: Wings of Liberty Mission 7: The Great Train Robbery
This mission is fairly simple and quite easy on all difficulties: you have to destroy the trains. In the beggining, split up your marines and scour the whole area for mineral/gas pickups and diamond backs.
Diamond back here.
Another one here.
Some zerg research here.
Make sure you're building units while scouring with your diamondbacks. You can go 2 ways: Massing up diamondbacks, which is a riskier strategy, or massing up marines with medics, which is usually better.
When you kill a train it drops a bunch of minerals and gas, make sure you pick them up.
There's more zerg research here.
There's another diamondback here.
And the last diamondback is over here.
After you have all the diamondbacks, either get marines+medics and make sure you get their armor and damage upgrade, or just mass up diamondbacks.
After the 5th destroyed train a force of hammer securities should start patrolling the area. If you have marines+medics they should be a piece of cake, but they might be quite problematic if you have diamondbacks.
After killing the last train, the mission will end.
The zerg research you get to choose does not really matter, depends on personal preference mostly.