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Map: sp_a3_speed_ramp.bsp Title: Propulsion Intro
This is the forty-second level of the game and the first part of Chapter 7. The level takes place within Aperture Science Enrichment Sphere #4, and introduces Propulsion Gel as well as the way in which it can be used in conjunction with Repulsion Gel. Goo is present as the primary hazard.
Fire a portal on the corner of the ceiling. Shoot the other portal on the floor below the Propulsion Gel and go through it.
Put the portal from the ceiling to the opposite side of the ramp. Push the Switch.
The runway should be now covered in Propulsion Gel. Run along it to reach the other side.
Then on the other side, fire a portal on the corner of the ceiling. Turn around and go forwards and fire the portal on the wall on the left and go through the portal.
Shoot the portal from the ceiling to the floor under the gel pipe.
Push the switch.
Use the first runway to get to the other side or use the portal on the floor.
Run along the second runway.
Fire portals to the right wall and to the left wall. Go through the portal and pick up the cube.
Go back and use the portal from behind the glass and put it on the beginning of the second runway. Go through the portal on the wall.
Fire the portal at the beginning of the first runway and get the cube on the button.
Get to the other side by using the runway.
Shoot a portal on the floor on the right. The other portal should be at the beginning at the first runway. Go through the portal on the floor.
Go to the end of the runway. Run along the runway and go through the portal. Push the switch.
Put the portal under the propulsion gel and the other portal on the pillar. Push the Propulsion Gel switch.
Wait until the gel has stopped flowing and then place the portals on the ceiling and under the Repulsion Gel. Push the Repulsion Gel switch.
Run along the runway to the catwalk. Go to the other side of the pillar and place a portal on the wall. Put the other portal above it. Go through the portal.
Go to the other side of the pillar and shoot the portal from below to the wall next to Propulsion Gel. Then go through the portal.
Fire the portal from the wall on the pillar and use the runway to go through the portal.
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