Even seeing the game in action, it was a bit tough to wrap our minds around what type of game Portal is. While it's all viewed from the first-person perspective, it definitely doesn't fit neatly into the FPS genre since, like, you're not actually shooting anyone. It's more of a puzzle game than anything else, although it's definitely a far cry from games like Lumines and Tetris. If the levels that we saw are any indication of what'll be in the finished product, you're going to forced to use the old noggin quite a bit.

Most of the levels that we saw required the player to figure out how to open a door, then exit the stage by walking through said door. It's much harder than it sounds. You'll need to figure out how to drop boxes onto pressure pads, redirect bouncing energy balls into catchers, and disable turrets without getting blasted by gunfire. Frankly, it's tough to even describe what went on during the demo. We saw the player jump through a portal and fall out of the ceiling, launch himself far into the air through one portal by jumping from a considerable height into the other, as well as a number of other fantastical feats of derring-do. The puzzles are incredibly challenging, especially when you haven't quite wrapped your head around what's possible and what's impossible (although there doesn't seem to be much that fits in that category).