Weak toBugGhostDark ×1.6

Attacker	Type	Moveset	DPS
Blacephalon	FireGhost	AstonishShadow Ball	32.5
Pheromosa	BugFighting	Bug BiteBug Buzz	31.3
Darkrai	Dark	SnarlShadow Ball	29.2
Chandelure	GhostFire	HexShadow Ball	29.0
Gengar	GhostPoison	LickShadow BallLegacy	28.9
Absol	Dark	SnarlBrutal SwingLegacy	28.3
Eternatus	PoisonDragon	Poison JabDynamax CannonLegacy	27.7
Dragapult	DragonGhost	AstonishShadow Ball	27.6
Hoopa	PsychicGhost	AstonishShadow Ball	27.1
Lunala	PsychicGhost	Shadow ClawShadow Ball	27.1
Gholdengo	SteelGhost	HexShadow Ball	27.1
Zoroark	Dark	SnarlFoul Play	27.0

Fog boosts the Ghost attacks above. Windy boosts Musharna.

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

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

Questions people ask

What is Musharna weak to in Pokémon GO?

Musharna takes 1.6 times from Bug, Ghost and Dark.

What's the best counter to Musharna?

Blacephalon with Astonish and Shadow Ball, worth 32.5 damage per second against Musharna's own defense. The full ranking is above.