Portal ([Intel] Article)

It seems simple enough: open an entrance portal on one wall and an exit portal on another, and pass through to complete tasks. The tests become fiendishly difficult, however, when you must use the portals to redirect deadly energy pellets toward their targets, or jump through a portal far below, so your momentum flings you out an exit portal toward a seemingly inaccessible area. GLaDOS promises you cake when you’re done, but something doesn’t seem right. What fate does she really have in store for you?

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