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Just Cause 2 Walkthrough The Roaches - Stronghold Takeover Mission 1: Free Trade
Just Cause 2 The Roaches - Stronghold Takeover Mission 1: Free Trade
Grapple your way to the other side of the gate. Then punch in the code to let The Roaches in.
Use the Grappling Hook to pull down the Sniper, or Grapple your way to the tower to fight him head on.
Use the Grappling Hook to pull the Mounted Gunner from the weapon -- this is the most effective way of dealing with him
Man the mounted gun to protect the technician.
You can detach the mounted gun to destroy the chopper, but if you want to use it for your own, you'll want to hijack it instead using the Grappling Hook. After taking care of the stronghold commander, the mission will be over.