Who is really worth to grail (cu fsn or herc)?

How much do you like them? And who do you like more? You should always grail for love, that way the boosts are more rewarding.

I've grailed both because I like both. Hercules is usually useful in more situations, but needs his bond lvl 10 CE to gain his super survivability. Cu is super survivable from the start and gets better as you drop his skills cool down. Cu is also cheaper to grail since he is a 3*.

In the beginning I really appreciated my grailed CU as he helped me survive tough challenges many times.

After leveling several other servants and getting a few new good ones, I barely use him anymore because even with two grails and attack max fou'ed his damage output is pretty low.

As far as I know Herc really shines at level 90 and stays relevant for much longer because he has such an insane damage as a Berserker. I don't have one, though.

For gameplay reasons it would be herc. He benefits most from the increased damage of being grailed having higher base stats to begin with.
Cu needs multiple Grails just for his damage to be par. His main strength is really just how broken protection from arrows is. Grailing him to high levels like 90 or 100 doesn't make him equal to 5 stars and 4 stars for damage output but rather just makes the meme builds where he solos more viable.

Fighting with archer, yes, Lv90 Herc <= Lv90 Cu
But besides of that,
lv90 Herc > Lv90 Cu
Castle of Snow lv80 Herc >>> max bond CE lv100 Cu, let alone lv90+ Herc.

Herc is always one of best berserkers. Basically, berserkers are more versatile in versing any class enemy, no matter farming high-hp little boss or multi-classes hard boss fight. Equipped with Castle of Snow, Herc can also be compatible with many teams, just like Cu alter.

Indeed Cu is the best durable servant. But 2 quick cards with limited performance (damage, NP and even star generation) reduced his offensive performance. In this case, Cu pro even do better job after strengthening.

Therefore, in boss solo fight that grailed Cu is shinning, since a critical reason that enemy's attack could charge his NP, and Cu use the NP as major source as damaging. Meanwhile Cu can choose his card in solo fight more "freely". However, grailed Herc can do the same job.

I have to say that I love Cu in FSN or other Fate series way better than Herc, but grail is not an abundant materials. Cu is worth to be grailed, if you like him, to lv100 is not a bad idea. But the grailing effect is not comparable as Herc in my opinion.

I have Nero, Cu and heracles, grailed three of them and it's nice to grail servant you love. Very fun to solo all things in the game using them.

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