16 literally colossus battles. Period.
Your main tools in SOTC are your sword, your bow, and your horse, Agro. Your sword is extremely useful because when you hold it up it will shoot out a beam of light in the direction of your next victim. Also, while next to or on your victim you'll be able to see their weak spots. Without it they are not visible. Your bow can be used to bring down certain colossi so you can get on them, but your main killing weapon is your sword. Lastly, Agro is your means of transportation. These colossi are big and the world is even bigger. It would take forever to run around it, but with the help of your horse you'll have a much easier time getting where you need to be.
Just from looking at this game you can tell thats it's beautiful. The world is huge. You could probably double your play time if you decided to explore around this place. Most impressive about it all though is the fact that it never [noticably] loads. You're game will never be stopped in the middle of a horse back ride with a loading screen. You can explore this whole place from top to bottom, left to right, or whatever with no breaks.
Next on the huge list is the colossus size. These things are very very big (with a few exceptions) and very very cool. They were designed so creatively I don't even know how to describe them. Each has a unique strategy and some take quite a bit of work....some also take luck, these are the more frustrating ones. I only encountered slow down issues a few times throughout the whole game. A few of the colossi were just a bit to much for the PS2 to handle it seems. All in all though I was quite impressed.
The actually gameplay feels a bit awkward at times. Controls felt a bit unresponsive at points and left me simply feeling hopeless. Also, some of the colossus were fairly difficult to find and left me wandering in circles aimlessly getting fairly upset and not wanting to play anymore. It's not very exciting riding a horse around without a known destination. The few wildlife (birds, turtles, lizards) that were thrown into the world were a nice touch though.
In theory this game is amazing, one of the best of all time. In actually playing this game is pretty good. It's minor flaws keep hold it back from perfection, although because of its creativity and beauty it's something everyone needs to experience. The time trials and hard mode are a nice touch to being as the games goes buy fairly quick (and more than twice as fast once you know how to defeat each colossus). You can also earn some really cool toys (items) from beating the time trials.
I say buy this game as oppose to borrowing it. Support the masterminds who made it and see if you can make it all the way up to the secret garden.