Weak toBugGhostDark ×1.6

Attacker	Type	Moveset	DPS
Blacephalon	FireGhost	AstonishShadow Ball	20.1
Pheromosa	BugFighting	Bug BiteBug Buzz	19.3
Darkrai	Dark	SnarlShadow Ball	18.0
Chandelure	GhostFire	HexShadow Ball	17.9
Gengar	GhostPoison	LickShadow BallLegacy	17.9
Absol	Dark	SnarlBrutal SwingLegacy	17.5
Eternatus	PoisonDragon	Poison JabDynamax CannonLegacy	17.1
Dragapult	DragonGhost	AstonishShadow Ball	17.1
Hoopa	PsychicGhost	AstonishShadow Ball	16.8
Lunala	PsychicGhost	Shadow ClawShadow Ball	16.7
Gholdengo	SteelGhost	HexShadow Ball	16.7
Zoroark	Dark	SnarlFoul Play	16.7

Fog boosts the Ghost attacks above. Windy boosts Armored Mewtwo.

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

Armored Mewtwo's moveset, stats and CP All counters Raid board

Questions people ask

What is Armored Mewtwo weak to in Pokémon GO?

Armored Mewtwo takes 1.6 times from Bug, Ghost and Dark.

What's the best counter to Armored Mewtwo?

Blacephalon with Astonish and Shadow Ball, worth 20.1 damage per second against Armored Mewtwo's own defense. The full ranking is above.