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
Gholdengo
SteelGhost
OFFENSIVE CHECK
View matchup
257.494
90.0%
Standard error 3.19 points
▾
252+ SpA Gholdengo Focus Blast vs. 252 HP / 252+ SpD Ferrothorn: 192-226 (54.5 - 64.2%) -- guaranteed 2HKO after Leftovers recovery
02
Heatran
FireSteel
OFFENSIVE CHECK
View matchup
105.215
89.1%
Standard error 5.25 points
▾
252+ SpA Heatran Eruption (150 BP) vs. 252 HP / 252+ SpD Ferrothorn: 700-828 (198.8 - 235.2%) -- guaranteed OHKO
03
Ursaluna
GroundNormal
OFFENSIVE CHECK
View matchup
32.71
89.0%
Standard error 5.47 points
▾
252+ Atk Ursaluna Fire Punch vs. 252 HP / 0 Def Ferrothorn: 300-356 (85.2 - 101.1%) -- 12.5% chance to OHKO
04
Charizard-Mega-Y
FireFlying
OFFENSIVE CHECK
View matchup
125.307
84.4%
Standard error 5.51 points
▾
252+ SpA Charizard-Mega-Y Overheat vs. 252 HP / 252+ SpD Ferrothorn in Sun: 1056-1248 (300 - 354.5%) -- guaranteed OHKO
05
Volcarona
BugFire
OFFENSIVE CHECK
View matchup
67.081
84.1%
Standard error 6.17 points
▾
252+ SpA Volcarona Flamethrower vs. 252 HP / 252+ SpD Ferrothorn: 436-516 (123.8 - 146.5%) -- guaranteed OHKO
06
Latios-Mega
DragonPsychic
OFFENSIVE CHECK
View matchup
44.093
83.6%
Standard error 7.25 points
▾
252+ SpA Latios-Mega Mystical Fire vs. 252 HP / 252+ SpD Ferrothorn: 272-324 (77.2 - 92%) -- guaranteed 2HKO after Leftovers recovery
07
Dragonite
DragonFlying
OFFENSIVE CHECK
View matchup
101.922
79.5%
Standard error 6.91 points
▾
252+ Atk Dragonite Fire Punch vs. 252 HP / 0 Def Ferrothorn: 292-348 (82.9 - 98.8%) -- guaranteed 2HKO after Leftovers recovery
08
Tornadus-Therian
Flying
OFFENSIVE CHECK
View matchup
158.305
71.8%
Standard error 6.04 points
▾
252+ SpA Tornadus-Therian Heat Wave vs. 252 HP / 252+ SpD Ferrothorn: 264-312 (75 - 88.6%) -- guaranteed 2HKO after Leftovers recovery
09
Zamazenta
Fighting
OFFENSIVE CHECK
View matchup
156.656
71.4%
Standard error 6.16 points
▾
252+ Atk Zamazenta Close Combat vs. 252 HP / 0 Def Ferrothorn: 320-380 (90.9 - 107.9%) -- 50% chance to OHKO
10
Charizard-Mega-X
FireDragon
OFFENSIVE CHECK
View matchup
108.342
73.4%
Standard error 7.07 points
▾
252+ Atk Tough Claws Charizard-Mega-X Flare Blitz vs. 252 HP / 0 Def Ferrothorn: 888-1048 (252.2 - 297.7%) -- guaranteed OHKO
11
Cinderace
Fire
OFFENSIVE CHECK
View matchup
29.052
76.4%
Standard error 7.88 points
▾
252+ Atk Cinderace Pyro Ball vs. 252 HP / 0 Def Ferrothorn: 636-748 (180.6 - 212.5%) -- guaranteed OHKO
12
Terapagos
Normal
DEFENSIVE CHECK
View matchup
135.527
71.0%
Standard error 6.63 points
▾
252+ Atk Ferrothorn Power Whip vs. 252 HP / 252+ Def Terapagos: 138-163 (35.9 - 42.4%) -- guaranteed 3HKO
13
Kingambit
DarkSteel
DEFENSIVE CHECK
View matchup
138.767
69.4%
Standard error 6.68 points
▾
0 Def Ferrothorn Body Press vs. 252 HP / 252+ Def Kingambit: 184-220 (45.5 - 54.4%) -- 52.3% chance to 2HKO
14
Zapdos
ElectricFlying
OFFENSIVE CHECK
View matchup
189.973
59.6%
Standard error 6.13 points
▾
252+ SpA Zapdos Heat Wave vs. 252 HP / 252+ SpD Ferrothorn: 288-340 (81.8 - 96.5%) -- guaranteed 2HKO after Leftovers recovery
15
Kyurem
DragonIce
OFFENSIVE CHECK
View matchup
141.642
62.4%
Standard error 6.93 points
▾
252+ SpA Kyurem Ice Beam vs. 252 HP / 252+ SpD Ferrothorn: 105-124 (29.8 - 35.2%) -- guaranteed 4HKO after Leftovers recovery
16
Urshifu-Rapid-Strike
FightingWater
OFFENSIVE CHECK
View matchup
93.612
67.5%
Standard error 8.28 points
▾
252+ Atk Urshifu-Rapid-Strike Close Combat vs. 252 HP / 0 Def Ferrothorn: 342-404 (97.1 - 114.7%) -- 81.3% chance to OHKO
17
Hatterene
PsychicFairy
OFFENSIVE CHECK
View matchup
106.378
64.8%
Standard error 7.81 points
▾
252+ SpA Hatterene Mystical Fire vs. 252 HP / 252+ SpD Ferrothorn: 244-288 (69.3 - 81.8%) -- guaranteed 2HKO after Leftovers recovery
18
Moltres
FireFlying
OFFENSIVE CHECK
View matchup
99.245
63.1%
Standard error 8.36 points
▾
252+ SpA Moltres Flamethrower vs. 252 HP / 252+ SpD Ferrothorn: 408-484 (115.9 - 137.5%) -- guaranteed OHKO
19
Iron Valiant
FairyFighting
OFFENSIVE CHECK
View matchup
67.585
62.6%
Standard error 8.31 points
▾
252+ Atk Iron Valiant Close Combat vs. 252 HP / 0 Def Ferrothorn: 342-404 (97.1 - 114.7%) -- 81.3% chance to OHKO
20
Melmetal
Steel
SOFT CHECK
View matchup
137.264
51.9%
Standard error 7.27 points
▾
252+ Atk Melmetal Superpower vs. 252 HP / 0 Def Ferrothorn: 246-290 (69.8 - 82.3%) -- guaranteed 2HKO after Leftovers recovery
21
Ogerpon-Wellspring
GrassWater
SOFT CHECK
View matchup
216.245
45.6%
Standard error 5.81 points
▾
252+ Atk Wellspring Mask Ogerpon-Wellspring Superpower vs. 252 HP / 0 Def Ferrothorn: 258-304 (73.2 - 86.3%) -- guaranteed 2HKO after Leftovers recovery
22
Diancie-Mega
RockFairy
OFFENSIVE CHECK
View matchup
93.455
56.1%
Standard error 8.53 points
▾
252+ SpA Diancie-Mega Mystical Fire vs. 252 HP / 252+ SpD Ferrothorn: 272-324 (77.2 - 92%) -- guaranteed 2HKO after Leftovers recovery
23
Garchomp
DragonGround
SOFT CHECK
View matchup
108.384
53.9%
Standard error 8.13 points
▾
252+ Atk Garchomp Fire Fang vs. 252 HP / 0 Def Ferrothorn: 248-296 (70.4 - 84%) -- guaranteed 2HKO after Leftovers recovery
24
Great Tusk
GroundFighting
SOFT CHECK
View matchup
143.049
49.5%
Standard error 7.13 points
▾
252+ Atk Great Tusk Close Combat vs. 252 HP / 0 Def Ferrothorn: 344-408 (97.7 - 115.9%) -- 87.5% chance to OHKO
25
Venusaur-Mega
GrassPoison
SOFT CHECK
View matchup
93.363
49.7%
Standard error 7.29 points
▾
252+ SpA Venusaur-Mega Hidden Power Fire vs. 252 HP / 252+ SpD Ferrothorn: 180-216 (51.1 - 61.3%) -- 92.6% chance to 2HKO after Leftovers recovery
26
Landorus-Therian
GroundFlying
SOFT CHECK
View matchup
175.671
45.6%
Standard error 6.37 points
▾
252+ Atk Landorus-Therian Earthquake vs. 252 HP / 0 Def Ferrothorn: 154-183 (43.7 - 51.9%) -- guaranteed 3HKO after Leftovers recovery
27
Corviknight
FlyingSteel
SOFT CHECK
View matchup
144.168
48.3%
Standard error 7.06 points
▾
252+ Atk Corviknight Brave Bird vs. 252 HP / 0 Def Ferrothorn: 130-154 (36.9 - 43.7%) -- 99.5% chance to 3HKO after Leftovers recovery
28
Tapu Lele
PsychicFairy
SOFT CHECK
View matchup
121.597
46.7%
Standard error 7.69 points
▾
252+ SpA Tapu Lele Hidden Power Fire vs. 252 HP / 252+ SpD Ferrothorn: 188-224 (53.4 - 63.6%) -- guaranteed 2HKO after Leftovers recovery
29
Ferrothorn
GrassSteel
SOFT CHECK
View matchup
111.579
46.6%
Standard error 8.11 points
▾
0 Def Ferrothorn Body Press vs. 252 HP / 0 Def Ferrothorn: 116-138 (32.9 - 39.2%) -- 9.6% chance to 3HKO after Leftovers recovery
30
Scizor-Mega
BugSteel
SOFT CHECK
View matchup
48.584
48.9%
Standard error 9.60 points
▾
252+ Atk Scizor-Mega Close Combat vs. 252 HP / 0 Def Ferrothorn: 254-300 (72.1 - 85.2%) -- guaranteed 2HKO after Leftovers recovery
Ranked #28 with 7.41% usage. Sorted by conservative score.