This game reminds me a lot of the arcade games where you rush to the bottom of what ever you are in, in this case a tower of ninjas. If you are using a keyboard and mouse, I feel bad for you. The controls on the keyboard and mouse are really horrible and don't feel right at all for this game. I suggest plugging in a wired 360 controller for it. The controls are perfect for the controller. I had no issues with rushing down a tower of death filled with skinny ninjas, fat ninjas, pigs, fish, dragons, and what looked like fat dogs that shot daggers from their mouths. It is a really fast paced game and the controls are dead on for it.
Rating: 10/10 for controller (2/10 for keyboard and mouse)
The game actually gives you a comic so you know what is going on in the story. There really isn't any events during the game besides at the end, which I will not spoil for you. Although, the creators were really smart with making you finish the game on Hard mode to get the real ending and additional levels. Wish all games did that. Although they give you a comic to understand what is going on, you don't need to actually read it to play the game. There aren't any secret things in the game that involve the story line.
I obviously can't give this game a perfect score because well, the game really doesn't involve the player in the story line, just plops you on top of a tower and tells you, get down to the bottom... if you can.