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Metagross

Metagross IVs — Attack 15 Required (Mirror CMP) · Master League

💯 CP 4286 · L50 · Season 28 (2026.09.08~12.01) · Updated 2026-10-09

Got a Metagross 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 Metagross, 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: 56W 44L.)

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 15/15/14
You start dropping Reshiram and similar. If you rarely face them (low real pick rate), it's fine to run.
❌
Don't build yet · Attack 14 or below
Metagross 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.)

56W56%44L
Palkia (Origin)642
Zacian (Crowned Sword)845
Zygarde (Complete Forme)424
Metagross500
Kyurem (White)167
Reshiram165
Xerneas688
Kyogre369
Dialga (Origin)691
Eternatus511
Ursaluna297
Kyurem (Black)627
Reshiram (Shadow)198
Lugia633
Lunala683
Zamazenta (Crowned Shield)572
Ursaluna (Shadow)340
Necrozma (Dawn Wings)402
Marshadow268
Zekrom590
Zekrom (Shadow)198
Necrozma (Dusk Mane)269
Lugia (Shadow)587
Palkia (Shadow)453
Ho-Oh359
Garchomp (Shadow)199
Metagross (Shadow)500
Groudon404
Melmetal712
Keldeo (Resolute)590
Garchomp413
Gyarados (Shadow)497
Kyogre (Shadow)505
Palkia479
Latios (Shadow)575
Keldeo (Ordinary)590
Rillaboom549
Yveltal356
Giratina (Altered) (Shadow)537
Florges688
Landorus (Therian)404
Solgaleo391
Dialga (Shadow)744
Meloetta (Aria)741
Primarina787
Dialga688
Gholdengo478
Kyurem613
Latios680
Dragonite (Shadow)779
Mewtwo (Shadow)508
Giratina (Altered)566
Groudon (Shadow)601
Hydreigon (Shadow)484
Goodra595
Ho-Oh (Shadow)346
Latias (Shadow)674
Gyarados404
Togekiss750
Tapu Lele575
Jirachi767
Latias694
Enamorus (Therian)683
Tyranitar (Shadow)593
Mewtwo572
Conkeldurr (Shadow)233
Dragonite468
Rhyperior (Shadow)578
Rhyperior648
Sylveon927
Heatran (Shadow)311
Genesect (Shock)502
Genesect (Chill)642
Raikou (Shadow)654
Baxcalibur715
Salamence (Shadow)593
Urshifu (Single Strike)398
Darkrai (Shadow)143
Kingambit561
Snorlax (Shadow)529
Hydreigon428
Volcanion281
Golisopod (Shadow)481
Urshifu (Rapid Strike)487
Tyranitar487
Heatran260
Raikou686
Golisopod402
Zapdos424
Zapdos (Shadow)481
Hippowdon (Shadow)183
Snorlax575
Annihilape738
Mamoswine (Shadow)738
Annihilape (Shadow)688
Zacian (Hero)892
Zamazenta (Hero)546
Genesect (Burn)389
Landorus (Incarnate)182
Kommo-o537
⭐ 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
Metagross⭐
Metagross (Shadow)⭐
Dragonite⭐
Tyranitar⭐
Opp also BB (L51) · +0W
none
※ 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 (Metagross vs Metagross)
Mine (atk 14) vs Foe (atk 15)
shields0
L
322
shields1
L
427
shields2
L
351

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).
IVs (Atk/Def/Sta)CPHPVerdictMatchups lost
15 / 15 / 154286172Perfectnone
14 / 15 / 154270172CMP loss
Palkia (Origin)Palkia (Origin)·shields1
15 / 15 / 1442761714 lost
ReshiramReshiram·shields0MarshadowMarshadow·shields0Palkia (Origin)Palkia (Origin)·shields1Genesect (Shock)Genesect (Shock)·shields1
15 / 15 / 1342651706 lost
ReshiramReshiram·shields0MarshadowMarshadow·shields0Palkia (Origin)Palkia (Origin)·shields1Kyogre (Shadow)Kyogre (Shadow)·shields1Genesect (Shock)Genesect (Shock)·shields1Genesect (Chill)Genesect (Chill)·shields2
15 / 15 / 1242551697 lost
ReshiramReshiram·shields0MarshadowMarshadow·shields0Palkia (Origin)Palkia (Origin)·shields1Kyogre (Shadow)Kyogre (Shadow)·shields1Mewtwo (Shadow)Mewtwo (Shadow)·shields1Genesect (Shock)Genesect (Shock)·shields1Genesect (Chill)Genesect (Chill)·shields2
15 / 14 / 154277172Fine
MarshadowMarshadow·shields0Genesect (Shock)Genesect (Shock)·shields1
15 / 14 / 1442671714 lost
ReshiramReshiram·shields0MarshadowMarshadow·shields0Palkia (Origin)Palkia (Origin)·shields1Genesect (Shock)Genesect (Shock)·shields1
15 / 14 / 1342561707 lost
ReshiramReshiram·shields0MarshadowMarshadow·shields0Palkia (Origin)Palkia (Origin)·shields1Kyogre (Shadow)Kyogre (Shadow)·shields1Mewtwo (Shadow)Mewtwo (Shadow)·shields1Genesect (Shock)Genesect (Shock)·shields1Genesect (Chill)Genesect (Chill)·shields2
15 / 13 / 1442581716 lost
ReshiramReshiram·shields0MarshadowMarshadow·shields0Palkia (Origin)Palkia (Origin)·shields1Genesect (Shock)Genesect (Shock)·shields1ZapdosZapdos·shields1Genesect (Chill)Genesect (Chill)·shields2
15 / 13 / 1342481708 lost
ReshiramReshiram·shields0MarshadowMarshadow·shields0Palkia (Origin)Palkia (Origin)·shields1Kyogre (Shadow)Kyogre (Shadow)·shields1Mewtwo (Shadow)Mewtwo (Shadow)·shields1Genesect (Shock)Genesect (Shock)·shields1ZapdosZapdos·shields1Genesect (Chill)Genesect (Chill)·shields2
15 / 12 / 1442491717 lost
ReshiramReshiram·shields0MarshadowMarshadow·shields0Palkia (Origin)Palkia (Origin)·shields1Kyogre (Shadow)Kyogre (Shadow)·shields1Mewtwo (Shadow)Mewtwo (Shadow)·shields1Genesect (Shock)Genesect (Shock)·shields1Genesect (Chill)Genesect (Chill)·shields2
15 / 10 / 1442311719 lost
ReshiramReshiram·shields0MarshadowMarshadow·shields0Palkia (Origin)Palkia (Origin)·shields1EternatusEternatus·shields1Kyogre (Shadow)Kyogre (Shadow)·shields1Mewtwo (Shadow)Mewtwo (Shadow)·shields1Genesect (Shock)Genesect (Shock)·shields1Genesect (Chill)Genesect (Chill)·shields2Raikou (Shadow)Raikou (Shadow)·shields2

Why attack 15 matters — CMP

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 Metagross loses that priority to an attack-15 opponent. In the sim, the attack-14 mirror came out 0-shield=loss, 1-shield=loss, 2-shield=loss. In a mirror-heavy meta, attack 15 is effectively mandatory.

Where win/loss starts to split

Metagross is IV-tight. Even dropping to 15/15/14 starts losing Reshiram. 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), 0. 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 4337 · L51

Best-buddying even a compromise improves every matchup and beats same-stat rivals.

Hundo record by shield count

shields 0
57W · 43L
shields 1
56W · 44L
shields 2
52W · 48L

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 Metagross?
Metagross is IV-tight, so an effective hundo (or very close) is safest. From 15/15/14 you start losing Reshiram. 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'.

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Metagross IVs — Attack 15 Required (Mirror CMP) · Master League | GBL Note