Level 5: Venus Nickel-Iron Mine
Enemies: Class 1 Drone, Class 2 Drone, Small Hulk, Super Hulk, Medium Lifter, Cloaked Lifter
This level has long, winding tunnels but is fairly easy to complete if you head straight for the keys and then the reactor core. Make your way forwards and take the paths to the left side to find the Blue Access Key. Head back the way you came to the small hub and go through the door on the right side that leads to the Blue Door.
Fly through to find the Yellow Access Key, then blast through the prison door. Activate the wall opposite to open the secret door to where the Hostages are being held.
Leave the blue area and then head towards the opposite end of the mine to where you began the level. Go through the door at the end to find the Yellow Door. Follow the tunnel down towards the lava and the Robot Generator to find the Red Access Key. There are lots of Shield Boosters so you shouldn’t have too much trouble with this area. Continue forwards to find the Red Door and the Reactor.
Reactor Core: There’s an Invulnerability just before the Red Door so destroying the reactor should be a breeze. The reactor is behind some grates so fly around to the side and destroy it
Exit: Back through the Red Door and then fly through the tunnel in the ceiling in the room with the Robot Generator.