Some skills have several parts to them but are leveled up as one skill. Such as shadowfiend, all the 3 first abilities are the same skill, but you can activate it 3 times. It's an odd way of doing it, but it works I guess.
Lvl cap is 25 if it's the same as DoTA I think. You get a couple levels that you put into stats as well, instead of just the skills. No idea why they do that instead of just working those into the heroes, but they want to stick to everything DoTA did.

