Got a Yveltal 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 Yveltal, 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: 67W 33L.)
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 Rayquaza and similar. If you rarely face them (low real pick rate), it's fine to run.
❌
Don't build yet · Attack 14 or below
Yveltal 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.)
67W67%33L
433
550
691
291
888
408
288
307
343
291
288
263
694
320
485
345
732
655
684
575
888
500
531
536
694
840
509
627
607
345
876
568
621
899
835
369
652
573
543
636
328
369
568
780
819
455
509
419
586
675
520
531
639
682
181
440
643
632
639
641
678
566
595
648
504
557
271
570
343
703
607
405
316
171
652
303
189
271
527
618
817
513
534
675
757
491
707
687
648
600
636
538
511
219
696
529
691
735
332
417
⭐ 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) · +2W
⭐
⭐
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 (Yveltal vs Yveltal)
Mine (atk 14) vs Foe (atk 15)
shields0
패
351
shields1
패
390
shields2
패
422
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 Yveltal 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
Yveltal is IV-tight. Even dropping to 15/15/14 starts losing Rayquaza. 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 2 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 27 (2026.06.02~09.09); when the season changes we re-run the full top-100 sim and update it.
⭐Best Buddy (L51) effectBB CP 4326 · 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
67W · 33L
shields 2
63W · 37L
Bottom line — attack 15 is non-negotiable (mirror CMP), IV-tight, aim high. Based on the Season 27 (2026.06.02~09.09) meta; updated when the season changes.
FAQ
Q. Do I need a hundo Yveltal?
Yveltal is IV-tight, so an effective hundo (or very close) is safest. From 15/15/14 you start losing Rayquaza. 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 27 (2026.06.02~09.09) 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 27 (2026.06.02~09.09)ScopeMaster League Top 100Shields0 · 1 · 2Level50 / Best Buddy 51Battle engineGBL Note Simulator (PvPoke-based)Baseline15/15/15Last calculated2026-09-01
✔ 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'.
