Any worth in using Gawain?

This is strictly with neutral enemies, servants being level 80 and 1000 fou'd, all skill activated and talking about NP5.

Salter already has way higher np damage than Siegfried or Gawain.
Under normal circumstances Siegfried Deals 28507 while gawain 2544.
By sun lit stages Gawain deals 33073 thanks to the buster up buff when condition meet (last 3 turn)
Dragon type enemies take 76969 from siegfried but his buster buff last 1 turn but it isn't tied to anything.

As you can see Gawain barely outdamages Siegfried.
Gawain do have a np charge skill which charges 20% np there is that. But with his upgrades Siegfried after using his np gets NP gain buff so he can also recharge pretty fast.

I won't say to burn him because maybe one day he will be potentially usefull, but if u don't need an aoe saber right now, then you can skip him now.

CCC will have him as an event bonus servant, but there aren't that many Lancer mob or if there are they are usually 1 per round with slightly high HP so you need Single target saber against them rather than AOE like Gawain

No, you can use him for the side effects of his NP, but none of his skills deserve to be levelled up, his first skill has no difference on the attack buff it gives, his second skill is Charisma E (6~12% buff) and his 3rd skill is a 1 turn guts/20% battery.
If he was your only AoE attacker he could be decent, but you have Salter (best AoE Saber) and Lancelot (best ST Saber) so there is no reason to use him unless you like him.

Thanks to his NP charge skill you can use him for daily 3-turn farming with a KScope very easily. However, since his NP damage is on the lower end I would bring him only on lancer days.
Salter is better by a long shot but she cannot charge her NP.

His regular damage on sunlit stages can also be pretty damn impressive, but these are all niche situations so you won't get that much use out of him. Still, I find him a bit better than Siegfried since he doesn't require Georgios or dragon enemies to be a half decent attacker.

Honestly he needs an NP interlude and a strengthing on his charisma to be good. Even then...he’ll still be a mess.

I use him to clear lancer hands (he gets the buster buff) but not for much else.

If you manage to np2 him then he’ll be more useable but I wouldn’t go out of my way to do that.

That said, he IS a CCC bonus servant and his facecards hit slightly harder than Fran’s so it’s worth raising him just to gorilla smash things and to get that Sakura chip bonus. (You could just keep him at lv 1 in your backline, but...)

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ok ok.... ahahhahhahahahhahahahahahhahahahahaha
..........................muahahahhahahahaha.... sorry, sorry....

ok.... i have burn 4 of him becouse i hate him since Fate Extra. so my advise would be to burn him.
but..... lets talk about this for a second.
Point 1, his np is useless.
Point 2, but his base attack is not half bad (if you dont have any 5 star at least)
his deck is not good for spam his below avarage np, but is good for a front BBB chain.
so if, and i say if, you want to make him worth, then you should make a team for this kind of play style.
i dont know, meaby crit? he is still a saber, with a zerker kit, but still a saber. he will get the star if you use caster to generate those star.with his above average attack and deck and crit hard...
still... if you have to do something like thet... just use your saberlot, or a musashi from the friend list right?

Since he can charge his own NP gauge (unlike any others sabers you have) he can be very helpful in 3-turn farming. Guess that's it.