Talk:Katsushika Hokusai/@comment-44792879-20200104105750/@comment-2234004-20200104152012

You generally grail a servant if you need the extra perfomance (for example, if a servant keeps doing damage low enough to keep the enemy alive on a sliver of health), want to maximize performance (like your main DPS) or just to flaunt your favorite servant around :P

10 extra levels is basically one extra NP level (more or less), so look at it that way; if you see yourself in one of the situations above, no regrets! I do suggest you wait and see however, I myself am saving my grails for low rarity servants should they need the buff in a pinch (I do have several saved for my waifu tho lol).