Just another test subject

You are some what good at using the portal gun and make it through the first series of challenges including test chambers 1 - 18. These consisted of faith plates, speed gels, gravity vortexes and light fields, but in test chamber 19 you see a back door to the test chamber and so you think of it as an escape area to the outside world. Unfortunately you find your self in a room full of deadly nero toxin and are shut in and killed.

Test