Portal

SPOILERS BELOW:

Portal summed up in two words:
Fantabulously amazing.

This game is fantastic, and unlike Episode Two, it is a whole, complete, satisfying game. From the opening scene, to the puzzling tests, and the hilarious commentary by the computer in between, this game is great.
The difficulty curve is just right, first introducing you to the mechanics, then allowing you to get comfortable, and then throwing cryptic challenges at you when you have motivation even when you're stumped.
The humor is spot-on and excellent, and a great incentive just to complete each puzzling task.
The portal gameplay-mechanic is fresh and well executed.
The story is revealed in just the right manner and ends at the right time.
The absence of any human characters and the striking white design of the corridors maintains the lonesome atmosphere and enhances your anticipation when you reach for escape.

This is by far the best game out of the Orange Box, and the best Valve game since Half-Life².

Portal
9.7 Cakes/10 Cakes