Half-Life/Power Up

This mission is your first encounter with the Gargantuan.

You will first need to approach the train control room found on the left. This is a simple run to the opposite side of the first room, and through the left path. You can stop at the first drop, then turn around to reach the power generator.

When you encounter vortigaunts near the explosive barrels, you can either attack them directly, or use a grenade to blast both of them. Open the silo, and climb to the top, where you encounter enemy grunts.

Continue down the corridor, and head to the left to reach the elevator. The bottom of the elevator has a few mines, which you need to walk around by diving into the water.

The power generator for the track will need to be fixed before turning it on. To reach it, walk down the spiral staircase to the semi-flooded floor. Break the boxes blocking the generator piston, and climb back up. Press the switch to activate the generator.

Return to the central area with the gargantuan, and walk into the large corridor he approached from. Run to the end, and flip the switch to activate the tesla coils, which will fry the large enemy. Take the door to return to the tram, and move it onto the central track.

Enter the track control room, and flip the switch, then use the tram to break open the barricade.