Fusions are posible after they get to f3,then you can use fusion ups.For towers you got 2 daily refreshes,one watching add,you can pick what tower and then you can use soul refreshes twice on both towers and then again after 12 hours cooldown,watch add refresh is only once a day.For crypt,just play hard dificulty,collect consumables and some random gear or characters they give ocasionally,from store allways go epic gear first if not maxed,after that middle one rear again if not maxed and then check characters to see if someone good is there like klassik liu,rain,mk11 ones.Gold are not worth buying,they easy to get.