Could you please explain some of the game mechanics?

Thanks! Actually, I thought more people would write something. :)

I'm being a bit cheeky, of course :p, but regarding luck... doesn't it also probably not directly determine the outcome?
Let's take, for example (purely hypothetically :D), Marbas level 40 + unicorn + skill for reflecting magic + boots for reflecting magic, which gives us a 100% chance to deflect magic. But in reality, I doubt it will be exactly 100%. Or is it calculated directly based on the numbers?