Difference Between DotA & LoL - 'n why you should roll LoL insteed of Dota
unique, account/summoner-level,masteries and rune system.
Got any questions feel free to ask.
It's 100% free to play, But you can get additional skins for your champions for something called Riot Points aka real money.
Also theres a in game money system, that you get every time your playing a game, that you can buy champions & runes for.
Might sound a bit complicated but it's easier then it sounds.