Okami is a beautiful, interesting game and will get the full review it deserves soon enough, but for now, I'm interested by its beginning. Or middle. Possibly end. I'm not entirely sure. Either way, the first major section of the game is either a bizarre, poor game design decision, or a brilliant subversion of the heroic form.
The storyline of Okami is fairly similar to most other fantasy-based games - there's an ancient evil, a rebirth of an ancient hero, a quest to discover magical items to defeat the ancient evil, and so on. That's all fairly straightforward, but what's not is that that part of the game ends after 10-15 hours of play. The Big Bad, an ancient many-headed serpent named Orochi, is the focus of the game's intro and the entire plot of the game at first, complete with prophecies and quests to get items to weaken him. Then, all of the sudden, before the player has collected all of their powers, they are suddenly pushed into Orochi's sealed cave, a long, puzzle and combat-filled dungeon complete with heroic music implying that this is indeed the final confrontation with ultimate evil.
There are a few clues that it's not quite the ending that it seems to be. The game offers a wide range of collectibles, as most action/adventures do, and the player certainly won't have a complete collection of magic, items, or the various other tchotches involved in Okami. But it's still not quite so overwhelmingly obvious that I wasn't concerned that I'd missed out on half the game.
This is, generally, poor game design. If the player feels like they've completed the game, they're more likely to shelve it. If there were a Star Wars game which involved the destruction of the Death Star and death of the Emperor, a final level involving wandering around Endor picking up the garbage probably wouldn't go over terribly well.
On the other hand, Okami isn't a terribly serious game, and there's plenty of reason to believe that the heroic fantasy faux-ending isn't so much a game design failure as it is an elaborate joke. In the game world, the ancient evil was vanquished by a legendary hero and a wolf-god sidekick. The player becomes the wolf-god Amaterasu, and the ancient hero's descendant, Susano, works alongside Amaterasu in order to defeat the Big Bad. In most games, the player would be Susano, fulfilling his destiny and defeating all evil everywhere, then hooking up with his sweetheart at the end.
The subversion comes from Susano's character. He's an incompetent boob and drunken layabout who is basically guilt-tripped into trying anything at all, and once he does make any attempt at being a heroic warrior, it's only the efforts of the player, who uses magic to make Susano appear competent, which make him succeed.
If the first part of Okami is viewed as Susano's story, it's an amusing satire of fantasy game tropes. The hero is a shiftless dreamer who is forced into action, and then, based entirely on the help of his sidekick, succeeds in destroying evil and getting the girl (his village's sake brewer). Amaterasu may spend a good 15 minutes defeating the Big Bad, but Susano skates in and does his super-secret evil-destroying technique which finishes an already-completed job.
Unfortunately Okami doesn't make its satire explicit, which leads me to wonder if the scenario creators intended to satirize generic game plotting at all, or if they just stumbled into an interesting concept and stumbled right back out with a bit of genre-savvy winking at the audience.