Mysterious Heroine X

Submit Feedback or Error
Start Discussion!
See All

Table of Contents


April Fool's
Chaotic Good
Max HP 12,696
HP Rank
Max ATK 11,761
ATK Rank
Base Atk1,817Base HP1,862
Max Atk 11,761 Max HP 12,696
Grail Atk 12,874 Grail HP 13,909
NP per Hit (%) 0.81%
NP when Attacked (%) 4%
Star Absorption 98
Star Generation per Hit 25.6%

Table of Contents

Servant Skills

Fire Support EX

Gains a delayed buff.
After 1 turn, chance to Stun all enemies for 1 turn.

Show Info
Stun Chance 60%62%64%66%68%70%72%74%76%80%
CD 10 10 10 10 10 9 9 9 9 8

Available from the start

Unlocks after 1st Ascension

Star of Saber C++

Grants self Invincibility for 1 turn.
Gains critical stars.

Show Info
Stars + 10111213141516171820
CD 7 7 7 7 7 6 6 6 6 5

Unlocks after Rank Up Quest (not available, ETA 2019/08), replaces Intuition C+

Galactic Meteor Sword C

Increases own critical star generation rate against Saber enemies for 3 turns.
Increases own attack against Saber enemies for 3 turns.

Show Info
Star Rate + 50%55%60%65%70%75%80%85%90%100%
Attack + 30%32%34%36%38%40%42%44%46%50%
CD 8 8 8 8 8 7 7 7 7 6

Unlocks after 3rd Ascension

Class Skills

Riding EX

Increase your Quick Card effectiveness by 12%.

Cosmo Reactor A

Increase your Critical Star Drop Rate by 10%.

Noble Phantasm

Secret Calibur A+

Deal significant damage to a single enemy.


Deal extra Special Attack damage to an [Altria Face] enemy.

Show Info

Secret Calibur

Sword of Unsigned Victory

Rank Classification Hit-Count
A+ Anti-Personnel 12

Deal significant damage to a single enemy.

Level 1 2 3 4 5
1200% 1600% 1800% 1900% 2000%
Overcharge Effect

Deal extra Special Attack damage to an [Altria Face] enemy.

Charge 100% 200% 300% 400% 500%
150% 162.5% 175% 187.5% 200%
Secret Calibur (Upgrade 1) EX

(Upgrade via Interlude Quest 3.)

Deal significant damage to a single enemy.


Deal extra Special Attack damage to an [Altria Face] enemy.

Show Info

Secret Calibur (Upgrade 1)

Sword of Unsigned Victory

Rank Classification Hit-Count
EX Anti-Unit 12
Effect Deal significant damage to a single enemy.
Level 1 2 3 4 5
1600% 2000% 2200% 2300% 2400%
Overcharge Effect

Deal extra Special Attack damage to an [Altria Face] enemy.

Charge 100% 200% 300% 400% 500%
150% 162.5% 175% 187.5% 200%

Assorted Info

ID 86
Cost 16
Gender Female
Growth Linear
Inst. Death Chance 38.50%
Damage Distribution Quick 10,20,30,40
Damage Distribution Arts 33,67
Damage Distribution Buster 100
Damage Distribution Extra 9,18,27,46
Damage Distribution NP 5,7,5,7,5,7,5,7,5,7,5,35

Attack / HP Growth

Stat Ratings

Interlude Quests

Quest Requirements Reward
Interlude 1
Chapter Completion: London

Ascension: 1

Bond: 3

Interlude 2
Chapter Completion: London

Ascension: 2

Bond: 4

Interlude 3
Chapter Completion: London

Ascension: 3

Bond: 5

Rank Up 1 (ETA 2019/8)
Chapter Completion:

Ascension: 4

Bond: 0

✔ = Available ✖ = Unavailable

Ascension Materials


Skill Enhancement Materials

1 → 2 200,000
2 → 3 400,000
3 → 4 1,200,000
4 → 5 1,600,000
5 → 6 4,000,000
6 → 7 5,000,000
7 → 8 10,000,000
8 → 9 12,000,000
9 → 10 20,000,000

Costume Dress Materials

Costume Cost Materials
April Fool's

Bond CE

Bond Level 1 2 3 4 5 6 7 8 9 10
Bond Pts Req. 3,500 8,500 7,000 6,000 2,500 292,500 360,000 340,000 320,000 315,000
Annihilation List

When equipped on Mysterious Heroine X,
All allies will inflict 20% bonus damage against [Saber] while on the field.

Table of Contents


On paper, MHX has a strong statsline. She has good attack for an Assassin, high NP Generation, and good Star Generation rate, along with a single target Noble Phantasm that has early Interlude boost. However, she is a complete disappointment in terms of her skills. Her skillset is so bad that it is essentially playing without any skills the majority of the time when using her, and you are better off treating her like a literal stat stick instead of a fully fledged Servant.

Starting with Fire Support; it has an extremely high cooldown, a one-turn delay (so you have to plan ahead when attacking) and even then its stun chance isn't even guaranteed, making it a nonfactor in a lot of fights due to its downtime and general unreliability. Instinct is pretty much a mediocre skill, although MHX does get a Rank Up quest later turning this skill into an invulnerability buff for one turn, which does a lot for her survivability. And last but not least it's her Galaxy Meteor Sword, which only works against Saber enemies (who you're better off just bringing Archers against instead for the bonus damage and damage reduction at all times). Her Noble Phantasm's overcharge effect is also quite terrible, as it hits a very specific subset of Servants and is pretty much worthless compared to other Servant's Overcharge effects.

All in all, MHX stats are good enough for her to function as a decent single-targeted Assassin, but due to how terrible her skillset is in general, setting your expectation a bit lower when using her would be reasonable.


  • Great NP generation thanks to a BAAQQ cards deck, high hits count on her Quick cards with Riding boost and high NP gain per hit
  • Good critical stars generation thanks to having high hits count Quick card and Quick NP, with two passive that boost Star Generation rate in Cosmo Reactor and Riding
  • High single target damage Noble Phantasm due to early access to her NP up Interlude and high base Attack


  • Terrible skillset all around:
    • First skill is unreliable and has high cooldown
    • Second skill is mediocre until Rank Up buff
    • Third skill is extremely niche and rarely finds its use
  • Niche Noble Phantasm's overcharge effect that is irrelevant most of the time
  • Lack of strong  and reliable steroids to boost damage output in general

Level Up Skill Recommendation

None of MHX's skills stand out. After her Rank Up her second skill turns into a very good survival skill, but until then each skill is somewhat equal in their value. 

Fire Support can be levelled if a Master wants more reliability from the stun effect. The cooldown remains too long for it to be used multiple times per fight. 

Levelling Intuition will only add a rather small amount of stars, even at max rank. The cooldown reduction is quite useful however, and after Rank Up, makes MHX one of the very rare Servants with an Invulnerability on a 5 turn cooldown. 

Galactic Metor Sword is quite powerful but affects only Sabers. For Masters intending to use MHX against Sabers this skill can be levelled first. 

Craft Essence Recommendation

  • Imaginary Around / Gandr / Holy Night Sign: Since MHX does not have any Quick performance buff outside of Riding but is quite reliant on it, these CEs will help her tremendously in everything she does
  • Guda-O / Knight's Dignity / Gem Magecraft: Antumbra: Due to her star generation capability, a Critical Damage boosting CEs will do a lot of good for her as she will frequently do Critical Attacks

Table of Contents

Other Info

Release Date Saber Wars Event
AKA/Alias/Nicknames MHX, Saber Killer
Country/Place of Origin Outer Space
Illustrator BUNBUN
Seiyuu (CV) Ayako Kawasumi
Series Back Alley Satsuki (4/1 Joke)



Valentine's CE


Limited - Can only be summoned during certain events

Table of Contents