Weak toPoisonGhostSteel ×1.6

Attacker	Type	Moveset	DPS
Blacephalon	FireGhost	AstonishShadow Ball	28.0
Eternatus	PoisonDragon	Poison JabSludge Bomb	26.1
Metagross	SteelPsychic	Bullet PunchMeteor MashLegacy	25.7
Chandelure	GhostFire	HexShadow Ball	25.0
Tinkaton	FairySteel	Fairy WindGigaton HammerLegacy	24.9
Gengar	GhostPoison	LickShadow BallLegacy	24.9
Naganadel	PoisonDragon	Poison JabSludge Bomb	24.8
Dragapult	DragonGhost	AstonishShadow Ball	23.8
Lucario	FightingSteel	Bullet PunchMeteor Mash	23.7
Nihilego	RockPoison	Poison JabSludge Bomb	23.6
Hoopa	PsychicGhost	AstonishShadow Ball	23.4
Lunala	PsychicGhost	Shadow ClawShadow Ball	23.4

Fog boosts the Ghost attacks above. Overcast and Windy boost Gardevoir.

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

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

Questions people ask

What is Gardevoir weak to in Pokémon GO?

Gardevoir takes 1.6 times from Poison, Ghost and Steel.

What's the best counter to Gardevoir?

Blacephalon with Astonish and Shadow Ball, worth 28.0 damage per second against Gardevoir's own defense. The full ranking is above.