Got a Marshadow you've been scraping XL for, and it didn't come out 100%? Before you power up — 30 seconds. We simulated the entire Master top 100 to see whether that spread is fine to build.
For Marshadow, attack 15 is effectively mandatory, and the IVs are tight, so a high catch is safest. Below is the result of running the Master top 100 through a battle simulator, plus the mirror and best buddy. (Hundo 1-shield record: 69W 31L.)
Compromise IVs
15/15/15
IV-tight — an effective hundo is safest. See the verdict below.
Build it or not — at a glance
✅
Just build · 15/15/15 (effective hundo)
This Pokémon is IV-tight — aim for an effective hundo (or very close).
⚠️
Conditional · around 15/15/13
You start dropping Zapdos (Shadow) and similar. If you rarely face them (low real pick rate), it's fine to run.
❌
Don't build yet · Attack 14 or below
Marshadow always loses CMP priority to the mirror at attack 14. Don't build it — wait for a better one.
🔬 Full-meta sim — all 100, who you meet & beat
1-on-1 battles vs the Master League top 100, per shield. Green = win, red = loss. (Rating 500 = even; higher = more comfortable.)
69W69%31L
464
715
623
731
750
445
319
459
750
373
553
771
750
674
674
771
720
701
500
445
750
731
588
228
348
771
701
410
715
709
610
607
715
551
771
709
604
305
440
267
647
540
750
226
459
750
771
618
771
782
341
416
631
410
379
408
782
396
401
677
701
744
386
580
289
739
782
752
790
275
733
685
685
548
760
637
731
672
774
486
365
488
645
545
669
771
626
454
500
505
642
397
639
556
602
518
733
685
889
510
⭐ Best Buddy (L51) effect — newly won matchups
Opponents you newly beat once best-buddied. The result depends on whether the opponent is best-buddied too, so both cases are shown.
Opp not BB (L50) · +4W
⭐
⭐
⭐
⭐
Opp also BB (L51) · +2W
⭐
⭐
※ The mirror and same-stat rival return to a tie when the opponent is best-buddied too (both L51). So Best Buddy only wins the mirror when the opponent isn't best-buddied.
Why attack 15 is mandatory — CMP
Attack decides priority. Attack 14 always loses to a same-stat rival.
vsMirror (Marshadow vs Marshadow)
Mine (atk 14) vs Foe (atk 15)
shields0
L
440
shields1
Tie
500
shields2
L
448
Verdict by IV spread (Master League sim)
💡 15/15/15 at the top is the perfect IV (best); rows go to lower IVs downward.
Perfect·Battle-equal= win/loss identical to a hundo (no disadvantage — just use it).
Fine= it only loses to weaker (non-top) opponents, so it's acceptable to run.
N lost= it starts losing to N strong top-10 opponents — a real disadvantage.
CMP loss= at attack 14 you always lose the mirror / same-stat rivals.
‘Matchups lost’ = opponents you newly lose to at that spread (0/1/2 shields = how many shields are used).
Master League has no CP cap, so everyone is max level. When same-species (mirror) or same-stat Pokémon fire a charged move on the same turn, the higher effective attack goes first (CMP). An attack-14 Marshadow loses that priority to an attack-15 opponent. In the sim, the attack-14 mirror came out 0-shield=loss, 1-shield=tie, 2-shield=loss. In a mirror-heavy meta, attack 15 is effectively mandatory.
Where win/loss starts to split
Marshadow is IV-tight. Even dropping to 15/15/13 starts losing Zapdos (Shadow). Across the full top-100 sim, small stat cuts cross breakpoints and flip matchups, so a high-IV catch is the safer play here.
Best Buddy — depends on whether the opponent is too
Best Buddy (level +1) depends on whether the opponent is best-buddied. Against a non-best-buddied opponent (L50) you newly win 4 matchups at 1 shield; against a best-buddied one (L51), 2. Top Master legendaries are usually best-buddied, so the mirror and same-stat rivals go back to a tie when both are L51. It never hurts, but it doesn't magically win the mirror.
Note that this line moves with the meta. If usage shifts or a new Pokémon arrives, the breakpoints move and a spread that's fine today can get shaky. This analysis is for Season 28 (2026.09.08~12.01); when the season changes we re-run the full top-100 sim and update it.
⭐Best Buddy (L51) effectBB CP 4268 · L51
Best-buddying even a compromise improves every matchup and beats same-stat rivals.
Hundo record by shield count
shields 0
56W · 44L
shields 1
69W · 31L
shields 2
75W · 25L
Bottom line — attack 15 is non-negotiable (mirror CMP), IV-tight, aim high. Based on the Season 28 (2026.09.08~12.01) meta; updated when the season changes.
FAQ
Q. Do I need a hundo Marshadow?
Marshadow is IV-tight, so an effective hundo (or very close) is safest. From 15/15/13 you start losing Zapdos (Shadow). That said, if those losses are low-pick-rate, the real impact may be small.
Q. Attack is 14 — can I just build it?
Not recommended. At attack 14 you lose CMP priority to the mirror and same-stat rivals — a fight that should be 50:50 becomes 0:100.
Q. How long does this hold?
It's the Season 28 (2026.09.08~12.01) meta. When the meta shifts, the breakpoints and the compromise line move, so we re-run the full top-100 sim each season and update it.
Method
BasisSeason 28 (2026.09.08~12.01)ScopeMaster League Top 100Shields0 · 1 · 2Level50 / Best Buddy 51Battle engineGBL Note Simulator (PvPoke-based)Baseline15/15/15Last calculated2026-10-09
✔ Calculated & analyzed by GBL Note
These verdicts come from simulating each spread against the entire Master League top-100 across 0/1/2-shield scenarios with the open-source PvPoke engine. If no matchup flips versus a hundo it's 'Perfect/Battle-equal'; if it only loses to weaker (non-top) opponents it's 'Fine'; once it loses to a top-10 opponent it's 'N lost' by the number of losses. Attack 14 loses mirror priority — 'CMP loss'.
