If you can have only one pt 5: Helena Vs Caster Gil!

I have both, Helena for much longer, but I have to side with Gil on this one.

As most know, Helena's massive downside are her skills' cooldowns. Party-wide 20% NP battery, 5 stars per turn plus 80% chance to boost her NP damage, and a 20% buff to all three card types for the whole party. At max level, it has a 7/9/7 cooldown. As such, I use her mainly for farming.

Gil has a +100% star gen buff, a 21% ATK buff, and a 30% Arts buff plus debuff success rate, all for the whole party. The lower cooldowns helps to be able to use it in longer fights.

The ATK buff and Arts Buff stack multiplicatively for better effect, and the Def Down on his NP further boosts the damage done by succeeding attacks or NPs.

The Star gen buff is vastly superior to an extra 5 stars per turn since it affects the whole party. Timed right and with the right Servants, it potentially gives 100% crit chance for the whole party for the next few turns. I used it with my Dantes and EMIYA's NPs once (no star gen boosting CEs, used as the first card and no Quick chain bonus for Dantes but EMIYA had his Hawkeye active) and got 68 and 63 crit stars respectively.

Helena isn't bad per se but I would use her more for farming rather than harder content, but Gil is overall better support especially for an Arts and/or Crit team.

Felt like this one is more of what you need. I have both, except my Castergil is still a Lv1 baby gil, and as we all know support caster list these days are filled with Merlin & Waver, maybe a few Tamomo too, so don't have much chance to play with Gil.

Anyway, I guess I go with Helena since she is more versatile and all rounder in my opinion. NP wise I guess they both do very similar thing except 1 gives def and 1 reduce enemy crits. I guess what sets them apart are their skills.

I go for Helena because she can provide support for any type of servant since she gives 3 different type of buff and all round NP charge. The star for every round is quite good, so equip her with 2030 and she'll give you decent amount of stars. I guess what hurts her is her CD, even Lv 10 needs 7 turn, so might need to consider the right mystic to help her there or any servants that have CD reduction skill.

Overall I think they both quite close as GIl have some really decent skills, but I just went for Helena because the skills are slightly more versatile and suited for most servants.

I'm choosing CasGil for this one. He works so well with arts teams with his impressive arts buff (30% at max level). But more importantly, he's able to generate a lot of crit stars with his second skill, something that arts teams tend to struggle to do.
I will admit his NP damage isn't that great, but I don't usually use his NP as a damage dealer. I mostly use it right after I use his second skill to generate enormous amounts of crit stars or just to lower the enemies' defense.

I feel like this isn't a fair comparison since they fill two very distinct functions.

However I'm going to have go with Caster Gil. Helena suffers from the issue of having one mediocre skill and massive cooldowns. Gilgamesh may be limited to arts support, unlike Helena, but gets far more value out of the buffs he provides and has more offensive utility for himself. Increased star drop rate, attack up, and arts up makes him the premier offensive arts enabler.

Quite the choice but still id go for helena

Her 1st and 3rd skill (team wide 20% np and QAB 20% boost) allows her to fit in almost any team so shed be a bit more versatile than casgil

+that 50% np boost gives her higher damage output than casgil albeit the 80% success rate,

Casgil on the otherhand shines best when paired with arts based servants, his atk and art boost is no joke + the stargen skill (which is better than the 5 star passive generation minus the np damage boost)

Id go with helena most of the time..... to hell with the long arse cooldown tho

CasGil for Arts crit comp

Gil is an amazing servant but while I bring Helena to almost every battle, everyday, Gil shines only in my arts crit team. So I have to be fair and pick Helena for this one. Mini-Waver with an AoE NP is unbeatable after all.

I will go with Casgil. Helena is a good servant with useful skills, but she has really long skill cool-downs (7/8/7). This is quite a major flaw. On the other hand, Casgil is a great art crit support. With 3 turn all arts up, all atk up, all star gen up, and an np that gives def up to all allies and def down to enemies, he has pretty much most stuff in a package. Furthermore, as others have stated in this thread, when his buffs stack up together, he is a very powerful offensive support. The star gen buff is one of the best in game, and it can generate a serious amount of stars.