So here it is another year gone by and incredibly... the game has gotten worse... When the game was fair and enjoyable, I didn't mind spending a few bucks for upgrades. But now, upgrades are pointless. Wave after wave of non essential tiles, are hurled at your enemies, powering up their special abilities, meanwhile you are forced to into bad tile decisions and watch any special attacks you use either miss, dodge, or render any attack pointless... Don't waste your money...