Portal (ポートル)

Portal is (essentially) a bonus game on the Half Life 2 Orange Box thing, on which are 5 games in total. And in my opinion of the disc overall so far, it's also the best game on the Half Life 2 Orange Box thing. It's based on the Portal Technology from Prey, hence the name, and takes it to into a more puzzle-based context (a move that works surprisingly well).

The game begins with GLaDOS, a seemingly innocent (if not slightly quirky) AI, guiding you through some kind of facility. You're taught the basics of the portal physics with pre-placed portals, and over the first couple of levels you gain and upgrade the Portal Gun, enabling you to place your own. From here on in the puzzles get gradually more taxing, and GLaDOS provides you with a range of quirky quotes as you play (such as the fact that the fully upgraded gun is worth more than the organs and combined yearly incomes of those who made it).

The game really begins when it's supposed to end, though. At the end of the last trial you're placed on an 'inescapable' path into a furnace (a fate similar to the Weighted Companion Cube who accompanied you on a previous trial, before being incinerated). Despite the looming certain death, your handy portal gun allows an escape route which puzzles GLaDOS to no end (you think she'd have noticed, considering she'd watched you overcome much trickier puzzles before now). After her futile attempts to capture you ("please lay on the floor with your hands at your side, and an agent will collect you... for your celebratory party; there will even be cake"), you escape into the underbelly of the facility, and have to find your way to GLaDOS (to destroy her!).

Scrawled on the walls are messages, presumably from previous escapees. Most guide you in the right direction, but some notify the player how "the cake is a lie", and are often accompanied by pictures of the Weighted Companion Cube. This probably sounds weird, but along with GLaDOS trying to persuade you that the whole death thing was a joke, the game achieves a great quirky feel that you rarely get from a game.

I guess what I'm trying to get at is that I enjoyed it. The ending theme is also amazing.