Agree with lolix, the tuesday and wednesday maps were the easier ones imo. I did use the max cr Shao though with this guide which I forgot costs one less than a max cost silver. I actually still don't have a CCed silver archer because I started the week before Shao event which was enough to get stars for perfect Shao no Shuka and just use her over any silver. Lots of guides use two reduced silver archers on maps (thinking of key kii) but I just have to change strat or usually extra power on Bashira or Spica will make up for cost. But then this guide didn't even have max unit lvls which I did before going for orbs. Perhaps you had a particularly low prince lvl to not survive to the healer deploy?