At least once a week, there is a thread about whether or not someone should Grail a Servant.
Almost every single time, the most common answer is the same: Do not Grail for gameplay.
So, before you start asking if you if it’s worth it to Grail a Servant, please consider the following.
While Grails aren’t terribly hard to come by thanks to events, they’re still one of the two rarest materials in the game, with the other being Lores.
If you Grail a Servant because you don’t have anyone else for that role, only to end up getting a Servant that is better than the Servant you Grailed in that role, then you will have wasted that Grail.
While Grailing a Servant does increase their stats, the increase in stats will very rarely amount to much of a difference. Grailing an SR to lvl 90 will not always give stats equal to an SSRs.
In terms of gameplay and filling their role, raising a Servant’s skills will usually be more effective than giving them a Grail.
Now, if you have a Servant that you enjoy using, and wish to improve their gameplay, then by all means, go ahead and Grail them.
If you have multiple targets for a Grail, and you’re wanting to know which would benefit the greatest from a Grail, then we encourage you to ask. (I would recommend asking in the General Support Thread.)
If you like a Servant, but you’re wondering whether giving them a Grail is worth it, well… The answer is usually “If you need to ask, the answer is no,” but I’m sure plenty of people would still be willing to discuss advantages and disadvantages.
Thank you for reading, and best wishes with your Grailing!
Edit: To clarify, if you truly do wish to grail for gameplay, such as with the frequently noted Dantes to lv 100 to increase his damage output, that’s perfectly fine. Just make sure you’re choosing a Servant that you actually enjoy using or use frequently.
Please do not go grailing a Servant that you dislike and never intend to use if you get someone better.