This is very cool. It did seem to come out of nowhere, but it has been in development for several years. The reviews have it pegged right, more or less, and I'm not going to regurgitate them here. While the game feels grand most of the time, it often betrays the small force responsible for it. It can't escape the indie feel, and that's not a bad thing per se. The disadvantage lies in some of the genre details which are somewhat bare. The inventory system, while adequate, won't set any trends. It also needs just a bit more polish on the context-sensitive controls, and a lot more polish on auto-targeting. There's nothing more frustrating than watching a road sign get covered with your arrows while 2 unsightly beasts close in fast. Wasting a special attack, against a door you're trying simply to open, happens less frequently, but it should never happen when the button legends have changed from weapons to handling actions. This at least I hope they address with a patch.
That's about it for negatives, however. The game is huge and beautiful. I love the art style (which can be easily checked online). Motion is very fluid (I can only speak for X360) with occasional stutters during autosaves and area changes. (By that I don't mean new screens; the game streams/scrolls smoothly at all times except while teleporting.) Discovering the entire landscape took me 2 days of heavy playing. There's a lot to see and do, with dozens of main and side quests. The tone is always whimsical, with some LOL moments here and there. I'm old and jaded, so I imagine many others will find it even funnier. There is a lot of voice recorded for the humorous dialog, which I'm sure has something to do with the 1GB download size.
The action can get intense, and it's all fluid and quite pretty. I can attest to the Diablo-style addiction, for me anyway. The puzzles are generally satisfying to solve, and if you stop having fun with any one of them, you can use fortune cookies (collectible here and there) to unlock some hints. Difficulty is adjustable. On the normal setting, it's more than challenging enough for me. I've died multiple times already, with only a couple of those deaths being cheap shots. There is a great deal of variety in the weapons. As you progress, you earn new abilities which involve combining some of them. I have yet to see all the special attacks. There are also many, many special potions and powers (in the form of "orbs") to keep things interesting. It gets hard to choose what equipment to keep and what to discard. (Diablo once again.) All in all, a terrific effort, and undoubtedly worth the asking price.