Rabbit's Reviews #315: Koyanskaya of Darkness (5* Foreigner)

Foreigners are basically wannabe Avengers. Like Avengers, they’re neutral to basically everything, although they lose out on class advantage against Rulers in exchange for resistance to Berserkers. This isn’t bad in theory, and Avengers tend to be among the best Servants in the game… but sadly, Foreigners don’t get the same love, by and large. Avengers get all kinds of fantastic innate bonuses that help make up for their lack of meaningful class advantage—super high attack, an innate damage modifier, great passives, et cetera—but Foreigners are not nearly as inherently advantaged. With one key exception (which I’ll address later), nothing in Foreigners’ bases make them substantially more appealing than any other given class, so they need really amazing kits in order to let them outshine the better Extra classes or Servants with class advantage.

Sadly, Koyanskaya of Darkness does not do that. While she has quite a bit of utility within her kit, at the end of the day, she’s a DPS, and as a DPS she doesn’t do enough to outweigh being in a generally weak class. Her kit is somewhat similar to Jiang Ziya’s, actually, in that she brings enough party utility to serve as a plausibly strong semi-support… but she is weaker in two important ways: first, her support value is only notable when supporting a very small group of Servants, and second, Buster has a broader array of valuable SSR supports than Quick does, which means players are less likely to need a semi-support, and less likely to have space in a team to slot her in, even within her own niche. As such, despite her splashable buffs, she’s primarily a damage-dealer. As a damage-dealer, though, she has good-but-unremarkable buffs and some neat niche utility. In exchange for this, she has bad cooldowns, weak synergy with her best support, situational damage output, and, of course, essentially no class advantage context. She’s a situational investment at best and not even especially valuable in those cases.

Koyan has middling stats for a Foreigner, with mid-low attack and mid-high HP. This isn’t a great starting point for a DPS, but at least she’s not Voyager (sorry Voyager). Foreigners are usually pretty good at star gen, but Koyan only has one Quick and her hit-counts aren’t abnormally high, so her star gen will feel more typical for her deck than for her class. Her NP gain, similarly, is a little better than average for her deck, though not substantially so.

For passives, Koyan gets the Foreigner-standard Entity of the Outer Realm, for some extra star gen and, more importantly, Van Gogh compatibility. This is the Foreigner advantage I alluded to above—Foreigners benefit from Van Gogh’s massive crit buffs, and Koyan in particular is a great component of Van Gogh teams specifically. Koyan’s other two passives are unique to her. NFF Service boosts Koyan’s damage against Wild Beast enemies, which only includes eight Servants at the time of writing but at least counts a decent number of generic mobs. NFF Service also boosts Koyan’s Arts performance a touch, helping her NP gain, and makes her debuffs more likely to land, which helps her consistency. Koyan’s final passive, Nega-Self, gives her a 20% chance to inflict buff block against Wild Beast enemies with her attacks. This is a 30% chance in practice, as NFF Service’s boost applies here, and unlike most effects of its type, it also applies to Koyan’s NP. Again, Wild Beast is a fairly limited niche, especially when you’re looking specifically at hard fights, but this does make Koyan something of a silver bullet for the small subset of fights where this passive applies.

For appends, Mana Loading is far and away the most important. Since Koyan has a 30% battery, she requires Mana Loading in order to loop reliably with Koyan/Koyan/Oberon and a 50% starting charge CE. Mana Loading is great in general and well-worth the investment. Koyan’s Extra Attack buff, meanwhile, is useful if you plan to use her in crit-focused teams, but otherwise it’s not a huge buff. Koyan’s specialty damage append gives damage versus Rulers, turning her into a pseudo-Avenger for the purposes of Ruler-killing. This is decent if you don’t have a favored Avenger, but given how accessible Salieri and Ranmaru are, this is probably not worth the coins.

Ascension Materials

Stage	Cost	Materials
2	100,000	x10 Void's Dust Open Void's Dust configuration options x10 Fool's Chain Open Fool's Chain configuration options
3	300,000	x10 Phoenix Feather Open Phoenix Feather configuration options x10 Black Beast Grease Open Black Beast Grease configuration options
4	1,000,000	x10 Claw of Chaos Open Claw of Chaos configuration options x10 Primordial Lanugo Open Primordial Lanugo configuration options
Max	3,000,000	x10 Tearstone of Blood Open Tearstone of Blood configuration options x10 Fragment of a Twinkling Star Open Fragment of a Twinkling Star configuration options

Skill Enhancement Materials

Level	Cost	Materials
1 → 2	200,000	x10 Proof of Hero Open Proof of Hero configuration options
2 → 3	400,000	x10 Evil Bone Open Evil Bone configuration options
3 → 4	1,200,000	x12 Homunculus Baby Open Homunculus Baby configuration options
4 → 5	1,600,000	x12 Mystic Spinal Fluid Open Mystic Spinal Fluid configuration options
5 → 6	4,000,000	x12 Giant's Ring Open Giant's Ring configuration options
6 → 7	5,000,000	x15 Reactor Core of Dawn Open Reactor Core of Dawn configuration options
7 → 8	10,000,000	x15 Tsukumo Mirror Open Tsukumo Mirror configuration options
8 → 9	12,000,000	x15 Fragment of a Twinkling Star Open Fragment of a Twinkling Star configuration options
9 → 10	20,000,000	x1 Crystallized Lore Open Crystallized Lore configuration options

Append Skill Materials

Level	Cost	Materials
1 → 2	200000	x10 Deadly Poisonous Needle Open Deadly Poisonous Needle configuration options
2 → 3	400000	x10 Claw of Chaos Open Claw of Chaos configuration options
3 → 4	1200000	x12 Black Beast Grease Open Black Beast Grease configuration options
4 → 5	1600000	x12 Primordial Lanugo Open Primordial Lanugo configuration options
5 → 6	4000000	x12 Cursed Beast Gallstone Open Cursed Beast Gallstone configuration options
6 → 7	5000000	x15 Mysterious Divine Wine Open Mysterious Divine Wine configuration options
7 → 8	10000000	x15 Vision Scales Open Vision Scales configuration options
8 → 9	12000000	x15 Egg of Truth Open Egg of Truth configuration options
9 → 10	20000000	x1 Crystallized Lore Open Crystallized Lore configuration options

As a Foreigner, Koyan doesn’t ask for any pieces or gems. Instead, she needs modest amounts of a bunch of different mats. She asks for a lot of gold and silver Lostbelt mats, which can pose problems to newer players especially. More established players probably won’t have too much trouble leveling her, though.

Koyan is an example of a Servant with a remarkably busy skillset that still manages to not actually do a whole lot. Recommended skill order is 1>2>3.

Koyan can farm in traditional Buster battery looping ways with Koyanskaya of Light/Koyanskaya of Light/Oberon. Koyan needs a 50% charge CE to do this, and she also needs Mana Loading maxed (although she can also use Kaleid if her damage is high enough). She uses her first skill on turn 1, relies on Koyan of Light batteries turn 2, and uses her first skill again in conjunction with Oberon on turn 3. She won’t be farming with other non-Arashlike setups, but this should work well enough for general use, especially for nodes whose enemies fall within Koyan’s various niches. Her damage isn’t spectacular, and there are plenty of better farmers, but she can work at least.

Koyan is a lot more interesting in CQs. She can work as a semi-support for Kemono Servants, and although she’s not great in that role, she’s an option for players without many Buster supports. There isn’t a specific team setup that makes this work well—instead, you can consider Koyan a sort of backup support to fill whatever holes you happen to have. You run her with a Buster DPS with the Kemono trait and whichever Buster support you do have and hope for the best. If you don’t have any Buster supports, I would suggest picking Merlin off your friend list—you’ll probably end up needing some sustain, and Merlin is better at stalling fights out than Koyanskaya of Light and Oberon are.

Koyan’s kit is a lot cleaner when she’s used in a DPS role. Koyanskaya of Light/Koyanskaya of Darkness/Koyanskaya of Light/Oberon is a decent burst team—not as good as… well, most other AoE Buster options, but not a terrible one. You can also run something like Merlin/Koyan/Castoria for a more stall-oriented team that gets better use of Koyan’s AoE battery and NP charge skill. You can also, as always, scale down to lower-rarity supports if you don’t have the meta options. Base Mash is actually a pretty good partner here, as Koyan will end up with substantial defense buffs in play, and Koyan can toss her Overcharge buff to Mash for even more defense.

Koyan’s best team, though, is without a doubt double Van Gogh. Van Gogh/Koyan/Van Gogh has massive crit damage on all three Servants. All three Servants benefit heavily from Koyan’s first skill, and Koyan’s Overcharge buff can strengthen the attack buffs on one of the Van Gogh NPs. Koyan’s curses can fuel extra NP charges for Van Gogh, too, as an added bonus. Van Gogh teams are also missing pierce invuln by default, and while this isn’t a huge deal given Van Gogh teams’ stability, the potential to maintain tempo even in the face of incidental dodges and invulns is a nice plus.

Koyan’s CE choice depends largely on how you plan to use her. In farming contexts, she needs starting NP CEs. Event CEs with 50% charge are ideal of course, but outside of that CEs that provide charge and damage are great. Aerial Drive, Holy Night Summer, Demonic Heavenly Princess, and Golden Sumo are all good choices. As a support, Koyan either wants starting NP (for easy access to the Buster debuff on her NP) or 2030 to help with crit enabling. In Van Gogh teams, Koyan has a lot more flexibility. Since she’s likely going to stick around for a while, CEs that don’t provide starting NP but instead provide other benefits can be good. 2030 still works here, although the stars may be overkill. Prisma Cosmos can help enable more frequent NPs, and CEs that provide non-crit damage buffs (such as Limited Zero Over) can increase the team’s tempo.

Koyan doesn’t have any obvious CC needs. Star gen CCs can be a good choice, as she has decent crit potential but few ways to gain stars. Some extra incidental star gen can let Koyan leverage her third skill more effectively, or help other Servants crit past Koyan’s star weight.

Koyan is not a great unit all-in-all, and levels don’t fix that. Unless you really love Van Gogh and plan to frequently use Koyan alongside her, I wouldn’t bother grailing this one. The resources are better spent elsewhere.

Koyan has enough about her that’s just sort of intrinsically strong that she avoids being out-and-out bad despite the confused and anti-synergistic nature of her kit. That said, she comes out looking no better than mediocre. She’s highly limited as a supportive unit and not even all that effective in-niche, while as a DPS she has limited Koyanskaya of Light synergy and struggles to keep up with most other AoE Buster options. She’s usable, at least, and her Van Gogh synergy props her up a little bit, but by and large she’s pretty meh. An easy skip for most players, at least gameplay-wise.

Overall: 7/10
Single-Target DPS: 4/10
AoE DPS: 7/10
Survivability: 4/10
Offensive Utility: 6/10
Defensive Utility: 3/10
Farming Usefulness: 6/10
Casting Meteor Swarm: 10/10