Weak toPoisonSteelFairy ×1.6

Attacker	Type	Moveset	DPS
Tinkaton	FairySteel	Fairy WindGigaton HammerLegacy	36.6
Eternatus	PoisonDragon	Poison JabSludge Bomb	35.6
Metagross	SteelPsychic	Bullet PunchMeteor MashLegacy	35.0
Naganadel	PoisonDragon	Poison JabSludge Bomb	33.8
Enamorus	FairyFlying	Fairy WindDazzling Gleam	33.8
Lucario	FightingSteel	Force PalmMeteor MashLegacy	33.2
Nihilego	RockPoison	Poison JabSludge Bomb	32.1
Tapu Koko	ElectricFairy	Volt SwitchNatures MadnessLegacy	31.7
Zacian	FairySteel	Metal ClawPlay Rough	31.4
Roserade	GrassPoison	Poison JabSludge Bomb	31.4
Dialga	SteelDragon	Metal ClawIron Head	31.0
Munkidori	PoisonPsychic	Poison JabSludge Bomb	30.8

Overcast boosts the Poison attacks above. Fog and Overcast boost Grimmsnarl.

Level 40, 15 attack IV, costed against Grimmsnarl's own defense and typing, one per evolution family.

Grimmsnarl's moveset, CP and shiny All counters Raid board

Questions people ask

What is Grimmsnarl weak to in Pokémon GO?

Grimmsnarl takes 1.6 times from Poison, Steel and Fairy.

What's the best counter to Grimmsnarl?

Tinkaton with Fairy Wind and Gigaton Hammer, worth 36.6 damage per second against Grimmsnarl's own defense. The full ranking is above.