Observed target KO or switch rate is upstream p: the fraction of relevant encounters where the target was knocked out or switched out. Standard error is upstream d. The conservative score is p − 4d. These ladder observations do not prove a set-specific counter.
How to read this table
Use encounter count and standard error to judge the sample. Damage estimates below use inferred sets and remain separate from the observed ladder metric.
#
Checker
Encounters
Conservative score
Target KO or switch rate
01
Zacian-Crowned
FairySteel
OFFENSIVE CHECK
View matchup
467.74
80.6%
Standard error 3.15 points
▾
+1 252+ Atk Zacian-Crowned Play Rough vs. 252 HP / 0 Def Arceus-Dark: 458-542 (103.1 - 122%) -- guaranteed OHKO
02
Marshadow
FightingGhost
OFFENSIVE CHECK
View matchup
198.734
69.9%
Standard error 5.59 points
▾
252+ Atk Marshadow Close Combat vs. 252 HP / 0 Def Arceus-Dark: 356-422 (80.1 - 95%) -- guaranteed 2HKO
03
Arceus-Fairy
Fairy
DEFENSIVE CHECK
View matchup
139.394
71.0%
Standard error 6.57 points
▾
252+ SpA Arceus-Dark Ice Beam vs. 252 HP / 252+ SpD Arceus-Fairy: 65-77 (14.6 - 17.3%) -- possible 6HKO
04
Eternatus
PoisonDragon
OFFENSIVE CHECK
View matchup
152.708
61.6%
Standard error 6.62 points
▾
252+ SpA Eternatus Draco Meteor vs. 252 HP / 252+ SpD Arceus-Dark: 160-190 (36 - 42.7%) -- guaranteed 3HKO
05
Groudon-Primal
GroundFire
SOFT CHECK
View matchup
389.342
41.2%
Standard error 4.26 points
▾
252+ Atk Groudon-Primal Precipice Blades vs. 252 HP / 0 Def Arceus-Dark: 237-279 (53.3 - 62.8%) -- guaranteed 2HKO
06
Kyogre-Primal
Water
SOFT CHECK
View matchup
128.111
51.0%
Standard error 7.61 points
▾
252+ SpA Kyogre-Primal Water Spout (150 BP) vs. 252 HP / 252+ SpD Arceus-Dark in Heavy Rain: 328-387 (73.8 - 87.1%) -- guaranteed 2HKO
07
Ho-Oh
FireFlying
SOFT CHECK
View matchup
351.93
37.4%
Standard error 4.42 points
▾
252+ Atk Ho-Oh Brave Bird vs. 252 HP / 0 Def Arceus-Dark: 184-217 (41.4 - 48.8%) -- guaranteed 3HKO
08
Mewtwo
Psychic
OFFENSIVE CHECK
View matchup
25.856
57.3%
Standard error 9.73 points
▾
252+ SpA Mewtwo Earth Power vs. 252 HP / 252+ SpD Arceus-Dark: 78-92 (17.5 - 20.7%) -- possible 5HKO
09
Deoxys-Attack
Psychic
SOFT CHECK
View matchup
33.893
51.8%
Standard error 8.58 points
▾
0- Atk Life Orb Deoxys-Attack Low Kick (120 BP) vs. 252 HP / 0 Def Arceus-Dark: 291-343 (65.5 - 77.2%) -- guaranteed 2HKO
10
Chien-Pao
DarkIce
SOFT CHECK
View matchup
97.19
51.6%
Standard error 8.73 points
▾
252+ Atk Sword of Ruin Chien-Pao Sacred Sword vs. 252 HP / 0 Def Arceus-Dark: 232-274 (52.2 - 61.7%) -- guaranteed 2HKO
11
Zygarde
DragonGround
SOFT CHECK
View matchup
252.683
36.6%
Standard error 5.20 points
▾
252+ Atk Zygarde Thousand Arrows vs. 252 HP / 0 Def Arceus-Dark: 115-136 (25.9 - 30.6%) -- guaranteed 4HKO
12
Arceus-Ground
Ground
SOFT CHECK
View matchup
134.319
42.2%
Standard error 7.22 points
▾
252+ SpA Earth Plate Arceus-Ground Judgment vs. 252 HP / 252+ SpD Arceus-Dark: 129-153 (29 - 34.4%) -- 3.1% chance to 3HKO
13
Yveltal
DarkFlying
SOFT CHECK
View matchup
494.027
24.6%
Standard error 3.25 points
▾
0- Atk Life Orb Yveltal U-turn vs. 252 HP / 0 Def Arceus-Dark: 130-153 (29.2 - 34.4%) -- 4.8% chance to 3HKO
14
Arceus
Normal
SOFT CHECK
View matchup
76.091
50.5%
Standard error 9.87 points
▾
252+ Atk Life Orb Arceus Double-Edge vs. 252 HP / 0 Def Arceus-Dark: 226-266 (50.9 - 59.9%) -- guaranteed 2HKO
15
Arceus-Dark
Dark
SOFT CHECK
View matchup
91.534
43.3%
Standard error 8.92 points
▾
252+ SpA Arceus-Dark Ice Beam vs. 252 HP / 252+ SpD Arceus-Dark: 65-77 (14.6 - 17.3%) -- possible 6HKO
16
Ferrothorn
GrassSteel
SOFT CHECK
View matchup
44.318
35.3%
Standard error 7.18 points
▾
252+ Atk Ferrothorn Power Whip vs. 252 HP / 0 Def Arceus-Dark: 148-175 (33.3 - 39.4%) -- guaranteed 3HKO
17
Lunala
PsychicGhost
SOFT CHECK
View matchup
50.273
44.1%
Standard error 9.77 points
▾
252+ SpA Lunala Moonblast vs. 252 HP / 252+ SpD Arceus-Dark: 150-178 (33.7 - 40%) -- guaranteed 3HKO
18
Necrozma-Dusk-Mane
PsychicSteel
SOFT CHECK
View matchup
227.943
20.7%
Standard error 4.55 points
▾
0- Atk Necrozma-Dusk-Mane Sunsteel Strike vs. 252 HP / 0 Def Arceus-Dark: 123-145 (27.7 - 32.6%) -- guaranteed 4HKO
19
Ditto
Normal
SOFT CHECK
View matchup
46.583
34.6%
Standard error 9.67 points
▾
Ditto vs. Arceus-Dark: 0-0 (0 - 0%)
20
Fezandipiti
PoisonFairy
SOFT CHECK
View matchup
28.466
29.3%
Standard error 8.53 points
▾
252+ Atk Fezandipiti U-turn vs. 252 HP / 0 Def Arceus-Dark: 112-134 (25.2 - 30.1%) -- guaranteed 4HKO
21
Giratina-Origin
GhostDragon
SOFT CHECK
View matchup
151.22
12.2%
Standard error 4.29 points
▾
252+ SpA Griseous Core Giratina-Origin Draco Meteor vs. 252 HP / 252+ SpD Arceus-Dark: 169-199 (38 - 44.8%) -- guaranteed 3HKO
22
Alomomola
Water
SOFT CHECK
View matchup
128.38
11.4%
Standard error 4.79 points
▾
252+ Atk Alomomola Flip Turn vs. 252 HP / 0 Def Arceus-Dark: 64-76 (14.4 - 17.1%) -- possible 6HKO
23
Chansey
Normal
SOFT CHECK
View matchup
25.205
27.9%
Standard error 8.94 points
▾
Chansey Seismic Toss vs. 252 HP Arceus-Dark: 100-100 (22.5 - 22.5%) -- guaranteed 5HKO
24
Rayquaza
DragonFlying
SOFT CHECK
View matchup
20.743
30.8%
Standard error 10.13 points
▾
252+ Atk Choice Band Rayquaza Dragon Ascent vs. 252 HP / 0 Def Arceus-Dark: 306-361 (68.9 - 81.3%) -- guaranteed 2HKO
25
Pheromosa
BugFighting
SOFT CHECK
View matchup
26.139
18.7%
Standard error 7.63 points
▾
252+ Atk Choice Band Pheromosa High Jump Kick vs. 252 HP / 0 Def Arceus-Dark: 624-734 (140.5 - 165.3%) -- guaranteed OHKO
26
Deoxys-Speed
Psychic
SOFT CHECK
View matchup
22.743
8.3%
Standard error 5.80 points
▾
252+ SpA Deoxys-Speed Icy Wind vs. 252 HP / 252+ SpD Arceus-Dark: 34-41 (7.6 - 9.2%)
Ranked #13 with 13.06% usage. Sorted by conservative score.