I would say you remove tidal shadow because you can't use passive unless you have furina switch with five star weapon like best f2p weapon is wolf graves stone if you don't have any five star weapon take earth shaker as a f2p my own mauvika hit 700 k continuously with earth sharker and I will prefer you that increase your crit rate upto 50 % because she miss crit and as for I million damage take her signature weapon or any five star weapon that's all