

Introduction
Mysterious Heroine XX is a 4-star servant in Fate/Grand Order with the Star attribute. Mysterious Heroine XX's class is Foreigner.
On the combined Fate/Grand Order tier list Mysterious Heroine XX is A tier, 105th of the 363 servants ranked, from where 3 community tier lists put Mysterious Heroine XX.
Other servants in Fate/Grand Order with the Star attribute: Altria Caster, Altria Caster (Berserker), Archetype Earth, Attila the San(ta), BB Dubai, Bedivere and 20 more.
Mysterious Heroine XX's banners
All banners- 7 November 2026 to 21 November 2026On the banner now, 100 Million Downloads Worldwide Mysterious Heroine X (Alter) Pickup Summon
- 24 July 2026 to 31 July 2026Swimsuit 2020 Revival BB Pickup Summon
- 12 September 2025 to 25 September 2025The Great Spirit's World Tour! Free Quest Backup Sakata Kintoki (Berserker) Pickup Summon
- 30 May 2025 to 4 June 202523 Million Downloads Altria Pendragon Alter (Rider) Pickup Summon
- 22 April 2025 to 28 April 2025"Pilgrimage Festival: Part 2" Mysterious Heroine X Pickup Summon
- 3 January 2025 to 5 January 2025New Year's 2025 Gilgamesh (Archer) Pickup Summon
- 12 October 2024 to 19 October 2024"Main Interlude: Great Void Sea Battle" Yang Guifei Pickup Summon
- 2 August 2024 to 8 August 2024Arctic Summer World! Edmond Dantès Pickup Summon
- 27 August 2023 to 28 August 2023Revival Swimsuit Servants BB Pickup Summon
- 24 October 2022 to 8 November 2022"Great Void Sea Battle" Pre-Release Campaign Pickup Summon (Daily)
- 19 July 2021 to 29 July 2021Revival: ServantFes Pickup 3 Summon (Daily)
- 10 August 2020 to 23 August 2020ServantFes Pickup 3 Summon (Daily)
Profile
Mysterious Heroine XX is voiced by Ayako Kawasumi in Japanese. BUNBUN drew her.
Stories
7Character details
A single shooting star that arrived to destroy the Servant Festival.
She is the voice of Space Law, and a merciless Machine Servant tasked with obliterating all of Earth's humans and Foreigners.
And when her unexpected identity is finally revealed, rumor is that the shock may overwhelm everyone!
Profile 1
Height/Weight: 154cm, 48kg
Origin: The Cosmo Guardian Trilogy
Region: The Servant Universe
Alignment: Lawful-Good
Sub-Attribute: Star
Gender: Female
*Height and weight changes every time she suits up or purges her armor.
"My weight is just high because of my work stress. I'll get back to my original 42kg real quick!"
Profile 2
『Etherspace, Yet Lawful』
Rank: EX
NP Type: Anti-Personnel
Range: 9 - 99
The Servant Universe Is the Cosmos.
Depending on her mood, she will shout either "Twinmyniad Disaster" or "Double X Dynamic," but this Noble Phantasm's True Name is "Etherspace, Yet Lawful." The True Name represents and mirrors the Rhongomyniad that protects the laws of space. The Rhongomyniad LR's safety limiters are removed, and it devastates Sabers by increasing its output. It'll blow its target up, planet and all.
She rejects the notion of a right to remain silent or a right to an attorney, because she is the voice of judgment. This is a useful Noble Phantasm that is not only a Special Attack against Foreigners, but also against Sabers.
Profile 3
『Nameless Nebula Sword, Secretmyniad』
Rank: EX
NP Type: Anti-Army
Range: 9 - 99
A galaxy nebula slicer that uses Rhongomyniad LR, a weapon said to be space's balancing scales. Swinging the spear around radiates light like a swirling nebula, which mows down all around it, friend or foe. This doesn't really get used in FGO.
Justice of World's End: A
Power from the boundary, the most advanced and furthermost area of space. It tears away at nothingness, and is the true principle behind expanding space. It offers all but unlimited power, able even to repel even higher beings from outside the universe in order to restore balance to the universe. XX...doesn't really understand how it works.
Profile 4
Suit Up: EX
The protection of the sacred spear armor Aahvalon. The armor constantly exists around XX in the form of spiritrons. With a speed of negative one second (where it can turn back time by one second to activate even if XX is taken by surprise) it protects and arms XX. She calls this little stunt "Suiting Up."
...Don't kid yourself, missy. This is actually an astonishing skill that XX acquired because she habitually overslept and was late for everything, even after joining the Galactic Police. It could actually be called a quick change skill. In fact, there's no real need for it, and it functions as armor in its spiritron state just fine. Arming oneself significantly increases their attack.
Police Instincts: E
Divine revelation used to find culprits. The low rank suggests it's really not so great for solving crimes, though. Various hints to solving crime seem to stem from otherworldly inspiration completely devoid of logic. XX never really notices these hints though. In some cases, this demerit becomes advantageous, actually making this a brilliant skill.
Profile 5
To sum up Mysterious Heroine X in a sentence would probably be simplest by saying that she is the protagonist of a TV comedy. By inheriting Altria's serious demeanor, X focuses on doing everything as quickly and simply as possible. Contrary to her polite and energetic mannerisms, she is extremely competitive (since she's not really aware of this, she is unbelievably dense). She challenged herself to achieve various things, and was absolutely relentless, not giving up until she succeeded. This was a bit problematic, but since she possesses such a virtuous nature, she ended up working to benefit others, so it all worked out okay.
However...
With the Servant Universe full and boiling over with an excess of Extra Classes, the balance between heroes and villains collapsed. The moment the scales of space tilted toward the villains, XX vowed to change her principles... And then the show headed into a new season. As an unemployed X didn't know what to do, she was hired by a secret society, the Galactic Police. In their HQ's center, she stumbles onto the oldest artifact in space, the Rhongomyniad. Her talents are acknowledged, and she becomes active as a Galaxian.
-Story Excerpt from CG Episode I-
Additional profile
When X became a member of the Galactic Police, she saw this as a good opportunity and changed her name and registration to XX. As she gained a new identity, she was able to abandon all her past debts, and she established Special Investigation Division O that cracked down on Foreigners, the invaders from outside space. And so was born XX, huntress of the wicked.
Her whole Saber-hunter thing has kind of faded, and now she's a Foreigner-hunter. Still, her desire to eradicate all Sabers hasn't gone away, so she still has her Saber special attacks.
Motivation, Behavior Towards Master:
Partner on Earth. A reliable wallet.
Since X has zero skills and awareness when it comes to romance, Master is more of a friend to her. Eventually, though, she realizes they are someone special.
"What's this sensation I'm feeling in my chest...don't tell me there's a wicked Saber on this planet!?"
Her erroneous thinking leads her to miss her opportunity. She's pretty much the same X, but she's aware that she's an officer, so tries to act more mature. Since she's a few versions later (read: older) than X, she looks like an office worker worn out by the daily grind.
Stats
- HP273rd of 41911,250
- ATK208th of 4199,751
- Star generation55th of 41915%
- Star absorption98th of 419147
- Death rate45th of 41910%
- NP gain per hit217th of 4190.64%
- NP gain when hit3%
At level 80. Each bar is measured against the highest value in the Fate/Grand Order roster, and the place is out of every servant with that stat, lowest first for Death rate.
HP and ATK by level
- HP
- ATK
Level 80 is the natural cap for a 4-star; 100 takes 10 Holy Grails and 120 another 20 grails plus Servant Coins, before Fou cards (up to 2,000 HP and 2,000 ATK) and Craft Essences.
Cards and generation
- Arts hits
- 3 (16/33/51%)
- Extra hits
- 4 (10/20/30/40%)
- Quick hits
- 4 (10/20/30/40%)
- Buster hits
- 4 (10/20/30/40%)
- Star generation
- 15%
- Star absorption
- 147
- Death rate
- 10%
- Party cost
- 12
- NP gain per hit (Arts / Quick / Buster / Extra)
- 0.64% / 0.64% / 0.64% / 0.64%
- NP gain when hit
- 3%
Skills
3
Suit Up EX
Skill 1LevelApply Invincible (1 turn) & increase ATK (1 turn) for yourself
- ATK Up (self, 1 turn)
- 50%
- Cooldown
- 5 turns

Police Instincts E
Skill 2LevelGain C. Stars + Decrease C. Star Gather Rate (1 turn) for yourself
- C. Star Gain (self)
- 20
- Critical Rate Up (self, 2 turns)
- 10%
- C. Star Gather Down (self, 1 turn)
- 100%
- Critical Rate Up (other allies, 1 turn)
- 10%
- Cooldown
- 4 turns

Justice of World's End A
Skill 3LevelApply Ignore Invincible (1 turn) & increase NP Gauge & apply Special Attack [Threat to Humanity] (1 turn) for yourself
- NP Gain (self)
- 30%
- Charge Gain (self)
- 1
- STR Up vs. Threat to Humanity (self, 1 turn)
- 50%
- Cooldown
- 5 turns
Noble Phantasm
Etherspace, Yet Lawful
Rank EX · Anti-Personnel · 4 hits · strengthenedIncrease your ATK (1 turn) <effect increases with Overcharge> + Deal significant Special Attack damage to a single [Saber-class Servant] enemy
- ATK Up (self, 1 turn, by Overcharge)
- 20%
- Damage (extra against the target trait) (one enemy)
- 1800%
Before the strengthening quest
Etherspace, Yet Lawful
Rank EX · Anti-Personnel · 4 hitsIncrease your ATK (1 turn) <effect increases with Overcharge> + Deal significant Special Attack damage to a single [Saber-class Servant] enemy
- ATK Up (self, 1 turn, by Overcharge)
- 20%
- Damage (extra against the target trait) (one enemy)
- 1500%
Class and append skills
Gain 2 C. Stars each turn & increase Debuff Resist for yourself
- C. Star Gain Per Turn
- 2
- Debuff Resist Up
- 4%
Increase your C. Star Drop Rate
- C. Star Drop Rate Up
- 8%
- Critical Rate Up
- 8%
Increase your Critical Strength
- Critical Up
- 10%
Increase your Quick Card effectiveness
- Quick Up
- 10%
Increase Extra Attack Card's effectiveness by 50% for yourself
Begin battle with NP charged at 20% for yourself
Increase ATK against [Moon Cancer] class by 30% for yourself
Increase Critical Strength by 30% for yourself
Apply a state that "reduces skill cooldown by 1 after using it" (1 time <2 times at Lv. 6-9, 3 times at Lv. 10>, goes into effect only 1 time per skill)
Ascensions and costumes
4
Ascension 1
Ascension 2
Ascension 3
Ascension 4
Materials
Ascension
- Ascension 1Materials:
Dragon Fang x8
Eternal Gear x8QP: 50,000 QP - Ascension 2Materials:
Black Beast Grease x8
Great Knight Medal x8QP: 150,000 QP - Ascension 3Materials:
Tearstone of Blood x8
Giant's Ring x8QP: 500,000 QP - Ascension 4Materials:
Dragon's Reverse Scale x8
Primordial Lanugo x8QP: 1,500,000 QP
2,200,000 QP for all four ascensions.
Skill enhancement (one skill)
- Level 1 to 2Materials:
Proof of Hero x8QP: 100,000 QP - Level 2 to 3Materials:
Dragon Fang x8QP: 200,000 QP - Level 3 to 4Materials:
Eternal Gear x10QP: 600,000 QP - Level 4 to 5Materials:
Great Knight Medal x10QP: 800,000 QP - Level 5 to 6Materials:
Aurora Steel x10QP: 2,000,000 QP - Level 6 to 7Materials:
Giant's Ring x12QP: 2,500,000 QP - Level 7 to 8Materials:
Primordial Lanugo x12QP: 5,000,000 QP - Level 8 to 9Materials:
Dragon's Reverse Scale x12QP: 6,000,000 QP - Level 9 to 10Materials:
Crystallized Lore x1QP: 10,000,000 QP
27,200,000 QP to take one skill from 1 to 10, 81,600,000 QP for all three. Append skills share the same table for their levels, paid in the same materials plus Servant Coins to unlock.
Append skill enhancement (one skill)
- Level 1 to 2Materials:
Octuplet Crystals x8QP: 100,000 QP - Level 2 to 3Materials:
Fool's Chain x8QP: 200,000 QP - Level 3 to 4Materials:
Claw of Chaos x10QP: 600,000 QP - Level 4 to 5Materials:
Black Beast Grease x10QP: 800,000 QP - Level 5 to 6Materials:
Mystic Spinal Fluid x10QP: 2,000,000 QP - Level 6 to 7Materials:
Mystic Gunpowder x12QP: 2,500,000 QP - Level 7 to 8Materials:
Reactor Core of Dawn x12QP: 5,000,000 QP - Level 8 to 9Materials:
Fragment of a Twinkling Star x12QP: 6,000,000 QP - Level 9 to 10Materials:
Crystallized Lore x1QP: 10,000,000 QP
Palingenesis (Holy Grails)
- 1Level cap: 85QP: 5,000,000 QP
- 2Level cap: 90QP: 6,000,000 QP
- 3Level cap: 92QP: 7,000,000 QP
- 4Level cap: 94QP: 8,000,000 QP
- 5Level cap: 96QP: 9,000,000 QP
- 6Level cap: 98QP: 10,000,000 QP
- 7Level cap: 100QP: 12,000,000 QP
- 8Level cap: 102QP: 12,000,000 QP
- 9Level cap: 104QP: 12,000,000 QP
- 10Level cap: 106QP: 12,000,000 QP
- 11Level cap: 108QP: 12,000,000 QP
- 12Level cap: 110QP: 12,000,000 QP
- 13Level cap: 112QP: 12,000,000 QP
- 14Level cap: 114QP: 12,000,000 QP
- 15Level cap: 116QP: 12,000,000 QP
- 16Level cap: 118QP: 12,000,000 QP
- 17Level cap: 120QP: 0 QP
Each summon of this servant gives 50 Servant Coins.
Bond
- 9,125Bond 2: 15,250Bond 3: 21,375Bond 4: 27,500Bond 5: 290,000Bond 6: 580,000Bond 7: 880,500Bond 8: 1,190,000Bond 9: 1,505,000Bond 10: 2,595,000
Total bond points to reach each level.

Apply 20% Special Attack [Saber] for all allies only if [servantName 2500300] (Foreigner) is equipped with this Craft Essence when she is on the field
Voice lines
81Home (5)
- Bond Level 1
- No talking in the interrogation room!
- Bond Level 2
- Can't talk while I'm on duty.
- Bond Level 3
- ...This planet just keeps on getting in the way of the investigation...
- Bond Level 4
- You're an honest human. That's good.
- Bond Level 5
- Maybe it's about time for me to get out of this gear.
Home (19)
- Bond Level 1
- Let me take this moment to express my appreciation. You're taking very good care of me, Master. Especially financially. I never knew Earth didn't accept Cosmo Currency... Before I formed a contract with Master, I had to stave off my hunger by sustaining myself!
- Bond Level 2
- Eh? I'm calmer and more reserved than before? Heh heh... Well, of course I am! I'm a full-fledged worker in society now! The old me that used to run wild is long gone now! There are good and evil Servants, after all. But if they're Sabers, I'll get rid of them no matter what!
- Bond Level 3
- Why did I join the force, you ask? Because the Servant Universe began its new season. Since I'm grown up now, I found a job with the Galactic Police and use my powers to protect space!
- Bond Level 4
- Hmmm, delicious! Thank you for treating me to Earth's specialty foods again! But to be honest, I'm not allowed to eat food from other planets because of sanitary concerns and quarantine. Eh? Do I think it's okay for a cop to ignore the rules? Fufufu...just because I'm a cop doesn't mean I should be bound by the law. After all, there are some evildoers who can't be defeated by legal means alone.
- Bond Level 5
- I meant to be an adult who would save Master, but instead I was the one who ended up getting saved... And while I feel it's spineless of me to allow it to happen, I don't know why my heart is racing. It makes me want to run away. (Gasp) Could this feeling be because...there is a Saber-class evil god somewhere on this world!? I know we're still eating, but you will have to excuse me! I'm just going to go save the planet real quick!
- Conversation 1
- It's time for your training. A light jog may be good for your health.
- Conversation 2
- About Master? Our relationship isn't really like a boss and a subordinate. It's more like a...friend? Oh, but since I'm now the older one, I must be the one doing the protecting!
- Conversation 3
- I may not be a Servant of this planet, but I will give it my all to support you. After all, Master's my bank!
- Likes
- What I like? Definitely holidays and local cuisine. Earth's specialty foods are so delicious!
- Dislikes
- I dislike Sabers.
- About the Holy Grail
- The Holy Grail... Oh, you're talking about the Reactor. I hear sometimes you can get one as a bonus. Ah! It grants wishes? That doesn't really matter. Just tell me whether it tastes good.
- Conversation 4
- I'm detecting an evil god! Be careful, Master. It appears there are some things here that threaten the whole world! Hm? But I don't really sense a strong Saber reaction... Guess it doesn't matter, then!
- Conversation 5
- This place has machine Servants!? Oh...Mecha Eli-chan? She's not a bad Servant? Well, it's not an evil god, but I am getting a similar reaction... Did you know that she falls under the same category as threats to humanity?
- Conversation 6
- Whoa! Look, look, Master! Look at the version of me in the blue tracksuit! She's so cool and dignified! That's me from two seasons ago, back when I was growing up so full of hope for the future and anxiety about so much around me. ...That brings back memories. Back in the those days, everyone who I met looked like Sabers to me, and I was the sort of heroine who was as dangerous as a sharp blade. Teehee... Oh, how did we ever deal with her!?
- Conversation 7
- Ex... Ex is here... That's Ex from back in the day... Oh crap, I'm getting all misty-eyed. I'm sorry, you'll have to excuse me for a minute...! And please keep my existence a secret from Ex!
- Conversation 8
- "All Sabers and Foreigners will be wiped out! This is the heroine's final form. Yay! So Cool!" That's the kind of reaction I want from this final Ascension, and there's not a thing wrong with it! So please, use that as your slogan! Now, come on, Master from Earth! Our next task is to go and take down Heroine ZZ! She's been running wild in the Horsehead Nebula!
- Conversation 9
- A brief moment of vacation...I mean, an assignment on Earth. In the beginning, I was a little jealous because I saw everyone around me enjoying themselves while I was slurping Cosmo Noodles at a campsite...but it's all a good memory now. And it's all thanks to you, Master. So, as the older one here, I should show off how generous I can be! As my way of saying thanks, I'll buy us some matching Hawaiian shirts. Tell me what style you like!
- During an Event
- There's an event going on...which means there's a festival with special food, right? Let's go, Master!
- Birthday
- Happy birthday. You've taken another step closer to adulthood. Maybe the distance between us has gotten smaller, too. Now, please hop on my spaceship. Today, I'm not going to be a cop. Instead, as your Senpai, I'm going to take you out for a special dinner.
Growth (1)
- Level up
- Take care of...my Spirit Origin...
Growth (5)
- Level up
- Energy at full charge! [id 2500300_1_G011]I'm brimming with motivation and spirit! You are a good Master!
- Ascension 1
- Phew! It's so hot in there! I can finally take this helmet off! [id 2500300_1_G031]Allow me to properly introduce myself! [id 2500300_1_G032]I am Mysterious Heroine XX. [delay 3.4]I am a Saber of justice from etherspace, here to pursue criminals! [id 2500300_1_G033]Eh? You know? [id 2500300_1_G034]But I'm slightly off? [id 2500300_1_G035]Ah-ha! So you're a fan of mine. Well thank you very much! [id 2500300_1_G036]But talking about all of that kind of thing will take a long while, [delay 3.1]so can we do that when I have a bit more free time?
- Ascension 2
- Hm. Not much has changed. [id 2500300_1_G021]What does that mean? [id 2500300_1_G022]Oh I see. So this is very similar to a salary, you say? [id 2500300_1_G023]That means I'm going to get a promotion for sure next time! I'll look forward to it!
- Ascension 3
- It's summer, so of course I'll change into a swimsuit! [id 2500300_1_G041]Blue skies, the emerald sea, [delay 3.6]and a crisp, refreshing breeze coming off the ocean. [id 2500300_1_G042]If you have a swimsuit as well, Master, then there's only one place for us to go! [id 2500300_1_G043]Yes! To a cheap, delicious pizza joint!
- Ascension 4
- I'm still getting used to this swimsuit. [id 2500300_1_G051]It really is nice to forget your duties and just rest sometimes. [id 2500300_1_G052]What do you think, Master? [id 2500300_1_G053]Do I look like a normal Sabe, I mean, a normal Altria in this getup?
First summon (1)
- Summon
- Hello, Master from Earth. I am Codename: XX. I have come to hunt down other Foreigners and Sabers.
Event (23)
- Battle Start 1
- Illegal Servant detected. Destroy.
- Battle Start 2
- You do not have the right to an attorney.
- Skill 1
- Charging complete.
- Skill 2
- Deploying Altrium.
- Skill 3
- Phew. Can't resist curry!
- Command Card 1
- -
- Command Card 2
- -
- Command Card 3
- -
- Noble Phantasm Card {0}
- Twinmyniad, disengaging safeties.
- Noble Phantasm Card {0}
- -
- Attack 1
- -
- Attack 2
- -
- Attack 3
- -
- Attack 4
- -
- Attack 5
- -
- Extra Attack
- I'll show you my true form!
- Damage 1
- -
- Damage 2
- -
- Incapacitated 1
- -
- Incapacitated 2
- -
- Victory 1
- All Sabers have been arrested. The rest doesn't matter.
- Victory 2
- Impressed? If I get even a little serious, it's so easy! Haha!
- Victory 3
- Halekulani's coconut cake is so good...
Event (23)
- Battle Start 1
- Codename XX, moving out!
- Battle Start 2
- It's okay. Leave it to me!
- Skill 1
- Need energy! Please show me some good places to eat!
- Skill 2
- I'm coming, criminal!
- Skill 3
- Please wait a moment. Summer's all about curry.
- Command Card 1
- Foreigner!
- Command Card 2
- I'll smash it!
- Command Card 3
- Time to work!
- Noble Phantasm Card 1
- This was my last resort... Well, I've been dying to use it!
- Noble Phantasm Card 2
- Let me show you an etherspace sword technique!
- Attack 1
- Toh!
- Attack 2
- Dynamic!
- Attack 3
- Let's do a trial match...
- Attack 4
- Haaah!
- Attack 5
- Double...X!
- Extra Attack
- Come, Aaahvalon!
- Damage 1
- I'm used to explosions!
- Damage 2
- Ouch!
- Incapacitated 1
- Work's done for the day! I'm off to see the sights in Hawaii!
- Incapacitated 2
- I knew it... I can't use my true powers...if I'm not a Saber... (Faint)
- Victory 1
- All Sabers have been arrested. The rest doesn't matter.
- Victory 2
- Impressed? If I get even a little serious, it's so easy! Ha-ha!
- Victory 3
- Halekulani's coconut cake is so good...
My Room (2)
- Noble Phantasm {0}
- The Servant Universe is the cosmos: etherspace, yet lawful. [id 2500300_0_B052]Here I go... Twinmyniad Disaster!
- Noble Phantasm {0}
- I'll be as restrained as I can, but I have to go all out! [id 2500300_0_B801]O light of the world's end, give me a bonus! [id 2500300_0_B802]Sabers must die! Double...X...Dynamic!
My Room (2)
- Noble Phantasm 1
- The Servant Universe is the cosmos: etherspace, yet lawful. [id 2500300_1_B052]Here I go... Twinmyniad Disaster!
- Noble Phantasm 2
- I'll be as restrained as I can, but I have to go all out! [id 2500300_1_B801]O light of the world's end, give me a bonus! [id 2500300_1_B802]Sabers must die! Double...X...Dynamic!
Voiced by Ayako Kawasumi. Illustrated by BUNBUN.
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