Obviously there is no such thing as a Shadow of the Colossus stamp, but one can dream can’t they. So much about this game has already been written, so let me discuss the most important element of it to me.
I feel that the game succeeds as interactive fiction. There’s so much freedom to aimlessly explore the word and in many respects, there’s no real reason to do so. But the key moment is the ending. You’ve spent SO much time in the game relying on your grip meter to hang on to the giant monsters you are trying to kill. Little do you know that killing these monsters was actually the wrong thing to do, and that you will have to pay the price for your transgression. Let’s watch shall we.
So here at the last you as you try to hang on for dear life, you watch that meter slowly drop to zero, knowing you are doomed to be sucked into the abyss. The moment works because you the player decide how long you want to hang on for. It’s the kind of moment you can only have in a game.