It can be. It's a different business model, but I like it. This is basically how it goes.
You pay 50$ for the game. You can then either go free to play (with a month of Immortal [explained later]) or pick some of the different paying models. I'm pretty sure they're all 15 $ a month and they add different types of 'advantages'. None of them affect if they will beat you or not directly. They are advantages such as ; better rested gold, run faster in safe areas, unlock all abilites, and a few more [these are the immortal benefits]. They're reason is basically this : everything in the game is available to all players. However players with less time and more money can buy their stuff rather than the player who has more time than money who can just farm it.
I prefer the farming because I feel like I earned them, and the 'farming' is just fighting. You go do a pvp match and you earn essence to buy skills with. There's no grind, unless you count grinding your opponents face off >.>