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- Bronze: 10
- Silver: 5
- Gold: 4
4 Portal Strategy
- Place a portal where the energy ball hits, but try to get where it makes impact as high up on the portal as you can. Using the squares on the floor to help you, you should fire a blue portal one and a quarter squares down from the black mark.
- If you stand at the door, you can get a good angle at firing an orange portal through the small gap. Try and get it as high up and as far to the left as you can. When this is done correctly (it may take a few tries), the energy ball should go straight into the receiver.
- When the ceiling door is open, fire an orange portal onto the ceiling, and, going through the blue one, you can drop onto the ledge.
- Lastly, fire an orange portal through the hole and drop down, go through the blue portal you made at #1, and you're done.