I do not love it, you just might.

In addition, you can from 7 different characters, which activates your time, take 3 into battle. These characters are very different with very different strengths and weaknesses. By repeatedly playing from levels gathers her experience (and money, but more on that later). From the experience Present your various skills.
This should be a clear that EXP grinding definitely this game is one who does not, and wants to play the same level over and over again, should not resort to this game.

Now the currency, of which there is, strictly speaking, two pieces and in various online recessions about this game, I also read a lot of criticism this.
The first currency is money, this one can only use to buy new weapons. One day, probably even armor should be implemented, currently there is no such however. Money you get basically at completing a level, no matter how good you were.
The second currency is red gems. These are on the one hand used to revive the characters to a level who have died in the level, on the other hand to need it also to buy to better weapons (along with money). Can revive Instead the characters you wait even one hour. The gems you gain when you complete a level with three stars.
That sounds combined now first bad, but characters die so rarely (if you play halfway intelligent) that this aspect almost disappears. In addition, you must always grind as much EXP that the money and the jewels come with time by itself together.
It makes no sense always the same to buy the next best weapon, I've just always saved everything and then buy the best weapon for a character. The outputting real money is not a problem, this is not a pay-to-win game, the only thing you achieve is with real money right from the beginning to have the thickest shootas.

In summary we can say:
If you grind nothing and makes her Mögt Tower Defense games, then accesses definitely.
Who does not want to grind that leaves it alone.

Edit: There is now a new patch, the additional levels and a endless mode adds. In addition, you can now skillen the characters new and there were introduced armor.