Ciel is a strange one. There are a lot of ways to use her, and most of them aren’t particularly obvious. Let’s walk through them all, shall we?
The simplest usage of Ciel is as a defensive ST Buster DPS for CQs. This works basically like any other Servant, and you have a few options for approaching it. The fastplay approach relies on using the typical double Koyanskaya strategy. Unlike most Busters, though, Ciel doesn’t particularly benefit from Oberon—she doesn’t need the extra charge, and she doesn’t make great use of extra NP damage. Ciel’s low base damage also means she’ll have trouble 3-turning fights, which makes Oberon’s various demerits more relevant than they would otherwise be. Ciel is pretty likely to survive until a second buff cycle, which means End of the Dream is not usually a good option for her.
Ciel has a couple of options for supports to bring in place of Oberon. The simplest one is to plug in Summer BB after using one of the Koyan’s skills on the first turn. BB can lock Ciel’s cards in place, guaranteeing you an NPBB chain three turns running. If what you want is consistency, and you aren’t short for damage, this is probably Ciel’s best option. If you do need more damage, though, you can use any other damaging support. Merlin is a good pick here, especially with his recent buffs—Ciel appreciates the attack, Buster, and crit buffs he provides. Reines is another good option, especially if you have her use her NP, as attack buffs are what Ciel is shortest on. If you use Reines, you can have her NP on turn 2, when you aren’t guaranteed Ciel cards anyway, to set up for a maximum-power turn 3.
The other way to approach DPS Ciel in a CQ context is as a stall Servant. The usual Buster Stall setups—Merlin/Castoria and Himiko/Castoria—will work well here, with the same pros and cons as usual. Himiko is better at negating all damage but has no way of restoring the supports’ health, while Merlin leaves you more likely to take hits but can also keep the team healed. I usually prefer Himiko, and given that Ciel both benefits from making sure she takes no damage at all and has ways of healing herself, I’ll affirm that recommendation here.
Note, though, that while Ciel can protect herself from debuffs and buff removal, she can’t protect her supports. In fights where those things are relevant, you’ll probably want to lean into fastplay setups—or run a double Koyan frontline, with a Castoria-fueled stall shell in the back to take over after the Koyans die.
Moving into less obvious uses of Ciel, Ciel has the distinction of being the only ST Servant (with the arguable and very situational exception of Bazett) with the potential to reliably farm AoE nodes. This comes with the caveat that this usually requires Summer BB, and enemy HP breakpoints have to cooperate, but Ciel can use her refund and card rigging to farm nodes that would usually require an AoE unit with 100% consistency. She can even reach 90++ viability in certain specific contexts! This isn’t necessarily useful, since you could also just bring a strong AoE instead, but it’s at least interesting, since it’s something no one else can do.
So, how does this work? The basic premise is that you’re using Koyan/Ciel/Koyan/Summer BB. On turn 1, you use all of one Koyan’s skills and plug her out for BB. Ciel uses all her skills, thereby forcing her cards, and BB uses Faceless Moon to lock Ciel’s cards for three turns. The other Koyan uses skill 2 and skill 3.
Ciel refunds 30% off her first NP, gets another 10% flat charge from her first skill, and gets 30% charge per Buster card. Against one enemy, Ciel either uses a BAB chain, if that will do enough damage to kill, or an NPBB chain otherwise. If the NP doesn’t kill, or if Ciel doesn’t have to NP, this leaves Ciel with at least 100% charge for the next turn. Against two enemies, Ciel does an NPBB chain, letting the NP kill one enemy and the cards kill the other. Again, this leaves Ciel with 100% charge. Against three enemies, Ciel does a BNPB chain, killing one enemy with the NP and each of the other enemies with a Buster. This leaves Ciel with only 70% charge, but you have batteries to spare, so this is fine. If you have to NPBB against a single enemy and the NP kills the enemy, Ciel is left with only 40% charge, which usually breaks this setup, but this should be an extremely rare case—it’s far more likely that Ciel farming will be prevented due to enemies having too much HP than by this specific situation.
On turn 2, you use the other Koyan battery. If you have Ciel’s fifth append unlocked, you also use Ciel’s first and second skills, saving her third skill for turn 3 in case you need the extra battery. Using S3 on turn 2 also cancels Faceless Moon, since it counts as a card shuffle, so it leaves you reliant on card RNG for turn 3, which defeats the whole purpose of farming with Ciel. Again, you do BNPB if there are three enemies, and NPBB otherwise. This time, Ciel gets 60% charge off using her NP alone: 20% total from skill 1, 20% total from skill 2, and 20% from the NP itself. Because of this, even if Ciel’s NP kills and there’s only one enemy, Ciel can secure the loop by using her third skill on turn 3.
On turn 3, you use the plug suit’s damage buff and, again, do BNPB or NPBB depending on the wave composition. Ciel should, generally speaking, be able to handle any node 90+ and below with this setup. An NP1 level 90 Ciel will do around 120k off her NP and about 180k off each Buster crit (a little less on the first, a little more on the second), which will typically be enough for 90+ nodes. A node with three high-HP enemies, or two weak enemies and one enemy with 200k+ health, might give her trouble, but, again, this is with no CE. Any CE that increases her damage will raise this threshold, as will grails, appends, NP levels, and class score. Note, though, that NP levels have much less impact on Ciel’s ability to hit farming thresholds than they do for most Servants, as Ciel’s NP is a relatively small portion of her overall damage.
You might also notice that, if focused on a single target, this is a lot of damage for an NP1 level 90 Servant to be doing at neutral. We can push it higher, too—Ciel’s best CE for farming, by far, is GudaGuda Poster Girl, which grants 60% attack up for three turns at base. With a non-MLB Poster Girl, maxed-out class score, append 4, level 100, and gold Fous, an NP1 Ciel can break a million damage against a single neutral target on wave 3. That’s without any sort of niche, too—she goes higher against Man, Archer, Demonic, or Avenger enemies. The big caveat to this is of course that you need Summer BB, as well as Poster Girl, which hasn’t been available for a long time. It also requires the final wave to only have a single enemy—her damage threshold drops a ton if she has to swing at more than one mob. Still, if you do have Summer BB and Poster Girl, Ciel is an extremely cheap option for handling certain high-end farming nodes.
She can potentially do this with worse CEs, too, provided she’s swinging at her favored targets. Under the same conditions but with Golden Sumo instead of Poster Girl, Ciel does just shy of 900k total on turn 3, meaning she’ll easily clear Archer enemies, and she should just barely clear Man enemies as well. She’s just shy of a mil against Demonic enemies, meanwhile, so NP2 should make up the difference. This does assume Moon Cancer class score unlocks soon, and also that you farm enough bond for two of Ciel’s appends, but the former seems likely to happen as part of the current event/story chapter, and the latter should be easier with the announced changes to earning coins through bond.
At the end of the day, you’re just doing something a dedicated counterclasser or a particularly strong generalist can do more easily, so the actual value of this in practice is questionable, but for the nodes Ciel works on, she works at surprisingly low levels of investment, which is worth noting—especially because ST units can’t usually AoE farm at all.
One other thing to note is that Koyan’s battery does come with an HP demerit, which functionally reduces Ciel’s crit damage on the turns Koyan uses the skill. Assuming you’re using the newer plugsuit, you can offset this on one of the turns by using its heal on Ciel. Usually you’ll want to do this on turn 2, as it makes a bigger difference once Ciel has stacked her second skill and HP thresholds are usually higher on turn 2 than on turn 1, but if you really need the extra damage on turn 1, you can use it there instead.
The use of the plugsuit’s heal does open up one other possibility. If you ignore BB and use Oberon instead, with an MLB Black Grail, an NP1 Ciel can do approximately 1.3 mil at neutral on turn 3. By using the plug suit’s heal on turn 3, you bring Ciel to max health for the final turn, and Oberon’s extra buffs coupled with the extra raw attack from Black Grail drastically increase Ciel’s NP damage, while also increasing the total damage on her crits. In exchange for this, Ciel loses access to her full crit buffs on earlier turns, and she can’t guarantee herself cards on turn 2. This means she can only reliably kill a single enemy on turn 2, and her turn 2 damage in general is drastically reduced. This won’t usually be feasible, but when it is, it’s a heck of a lot of damage to be able to guarantee. For just the right node, Ciel might be able to manage an X/1/2 90++, using a BNPB chain. Especially against a Saber enemy, the first Buster plus the NP can potentially kill the main enemy, leaving the second Buster and the Extra for the second enemy. This would take a highly specific node, and we don’t get 90++ nodes often enough to guarantee this will happen… but it’s not impossible, and it’s worth keeping in the back of your mind, just in case.
Outside of all this nonsense, Ciel can also be used as a tech pick for her ability to rig another Servant’s cards. This will only be useful to a handful of Servants, but in cases where getting a guaranteed brave chain on turn 1 with the potential for another on turn 2 or 3 matters, this may be worth it. If you were to, for example, use Ciel’s third skill and plug her out for a strong Berserker, like Arjuna Alter, you guarantee yourself a BBB or NPBB chain on the first turn, and if you’re lucky you can get another on the next. This isn’t normally possible outside of good card luck paired with sacrificial support strats, which makes it an interesting option, even if the standard Koyan/Koyan/Oberon strategy is usually better.
You can also pair a plug Ciel with Summer BB to lock any other Servant’s cards for three turns. This limits you to only one “proper” support, which means it’s probably not practically useful in most cases—you sacrifice a ton of damage for it—but if you really want to be sure someone like Bazett, Aoko, or Super Orion can spam their cards, this is an option.
For Aoko in particular, this enables card-based farming with 100% consistency. If you run Koyan/Ciel/Summer BB/Aoko, you can use Ciel’s S3, plug her out for Aoko, use Aoko’s first and third skills, use Koyan’s first and third skills, use Aoko’s first skill again, and then use Faceless Moon. You do an NPBQ chain with Aoko, using the NP to shift forms and then the AoE Buster to wipe the wave. On the next wave, you use Koyan’s second skill for more stars, and then whatever card chain lets you spend the fewest magic bullets—BAQ, ABQ, or QAB, depending—to clear that wave. On wave three, you use Aoko’s first skill a third time, then do an NPQB chain for maximum damage output. This does require a starting charge CE on Aoko, and it’s nowhere near 90++ levels of damage, but it’s pretty reliable for 90+ and lower, which is a neat trick. From a pure efficiency standpoint, you’d be better off just farming with Ciel herself (let alone a more conventional farmer), but since this setup doesn’t use any duplicate Servants, you can get away with grabbing any of them—even a maxed-out Aoko—off support, which could be handy for someone with a very specific box.
The larger point is that with a bit of creativity, Ciel’s ability to draw her own cards can enable certain strategies and teams that were not possible before. These strategies aren’t likely to be better than conventional alternatives, but it’s always neat when a Servant enables something new.
As I alluded to above, Poster Girl is far and away Ciel’s best CE for fastplay. With no in-kit attack buffs and with no attack buffs coming from her favored support, Ciel really appreciates the 60-80% attack up the CE provides. It’s such a huge boost that it more or less single-handedly makes her 90++ viable for x/x/1 nodes. That said, Poster Girl is a huge ask, as it hasn’t been on rate-up in ages, so until and unless it returns, it’s not really fair to count that towards Ciel’s overall performance.
Outside of that, Gold Sumo is Ciel’s best CE in most cases. If maxed out, it gives a flat 2000 attack, plus another 15% attack up. Because this applies to both Ciel’s NP and her cards, it’s actually better for fastplay than usual options like Cranking—NP damage up just doesn’t help Ciel that much, proportionally.
The elephant in the room is Black Grail. BG is usually the best CE for damage, and you’d think that Ciel, with her passive HP gain and easy NP access, would love it. Unfortunately, BG is a bad proposition for Ciel on several fronts. It doesn’t help her cards as much as something like Sumo, for one thing, and that’s where most of her damage lives. For another, BG’s demerit happens after passive healing, meaning a BG Ciel will almost always be below max HP, blocking her from accessing her full crit buff. This is enough to make BG essentially nonviable for farming, unless you’re committing to Oberon instead of BB and are willing to sacrifice early turn damage for a truly explosive wave 3.
In CQs, the calculus is slightly different. If you’re mostly going to be relying on spamming Ciel’s NP, and if the fight is going to last long enough that you aren’t going to be constantly rigging Ciel cards, and if you’re not confident in your ability to keep Ciel at max health, BG’s NP damage buff starts to look like a more appealing proposition. Essentially, in cases where you are more reliant on NPs than crits and where you can’t keep Ciel at full health anyway, you might consider BG. Otherwise, go with Sumo, or with Poster Girl if you have it and are going for a min-turn.
On the one hand, Ciel is flush with crit buffs, and getting a tiny bit more from CCs won’t help her that much. On the other hand, even a little more damage on Ciel’s cards may be enough to let her clear a CQ or farm a node. There’s very little reason not to stick crit damage CCs on Ciel’s cards. The other option is to lean heavily into antigimmick and stall—you can give her healing, defensive tools, buff removal, and so on—but most of the time you’ll be better off just pushing her damage as much as you can.
Introduction
Moon Cancer
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