I think hero gems will save between all Fate banners, and if they do save you should at least do your guaranteed summons on the banners you want the units from and then pity shirou. This will allow you to have a decent chance from atleast getting another unit rather than pitying one 👍
Yeah but u need to farm dark orb which will be a little hard for new player to accumulate,but if u can ascend her then she does really good dmg (bcs of the super crit)