Siphon Site D

Defense Points: 1000

Enemy Spawn Point (Ground): Three

Enemy Spawn Point (Air): One

Target to protect: One main, one sub-core

You have to defend the Main Core and the Sub Core. There's a Fire trap can help protect the sub core from the South Corridor. Blockade the path right outside the fire trap's range for good efficiency.

There's a Gas Trap valve to the south as well to hinder enemies from the East Causeway. And the same time, there's a Water Trap valve that will help block enemies from the Lower Chambers or sweep them away.

The path from the Upper Ledge doesn't have any traps so you may want to place a blockade along the stairs.

Another Gas Trap valve is found along the stairs to the north, leading to the main core. You can use the pipes to run around. Long range strikes can also activate the levers and valves.