All Purpose Training
Ah, you're back for more suffering. How delightful. This next series of tests will strain your decision-making and creativity. Make the 'right' choices, use your enemies as tools, and push your endurance to new levels of futility. Immerse yourself deeper in the world of Portal, and let's see how long you last. Remember, your failures are my greatest pleasure. Proceed, test subject. Amuse me.